Showing papers by "Tulane University published in 1973"
TL;DR: Polypeptides isolated from hypothalamic tissue selectively stimulate or inhibit the release of anterior pituitary hormones and melanocyte-stimulating hormone.
Abstract: The molecular structures of several polypeptides isolated from hypothalamic tissue have been established and the synthesis of these compounds has been achieved. These polypeptides selectively stimulate or inhibit the release of anterior pituitary hormones and melanocyte-stimulating hormone. Various studies indicate their important physiological role and support the concept that some of these polypeptides are hormones. Some synthetic hypothalamic hormones and their derivatives may find important clinical and veterinary applications.
486 citations
TL;DR: The synthetic growth-hormone-release inhibitory hormone inhibits G.R.R.-I.H. response to insulin-induced hypoglycaemia without affecting the prolactin or corticosteroid responses, but the effects are short-lived.
269 citations
TL;DR: Repeated injections of synthetic LH-RH decapeptide, adsorbed on polyvinylpyrrolidone and emulsified with complete Freund's adjuvant, resulted in the production of a specific antiserum to LH- RH in 2 of 3 rabbits.
Abstract: Repeated injections of synthetic LH-RH decapeptide, adsorbed on polyvinylpyrrolidone and emulsified with complete Freund's adjuvant, resulted in the production of a specific antiserum to LH-RH in 2 of 3 rabbits. The animals which produced this antiserum showed a reduction of pituitary LH content and marked atrophy of the testes. The antiserum-antibody complex was detected by the complement fixation test. The antiserum was capable of binding 125I labeled LH-RH. After iodination of LH-RH (using 125I and either the chloramine T or lactoperoxidase method) separation of the iodination products on CMC yielded 3 main peaks of radioactivity: The first was free iodide, the second was labeled peptide with low immunoreactivity, and the third was immunoreactive peptide. This 3rd peak consisted of 2 or 3 subpeaks; the leading subpeak(s) were more readily bound by antiserum than the trailing one(s). Binding of these fractions to antiserum was increased in the presence of small amounts of unlabeled LH-RH (a phenomenon c...
175 citations
TL;DR: In this article, the authors define an epimorphism as a map f: A → B such that for any maps g: B → C, h: B→ C, if g ≠ h, then gf ≠ Hf.
Abstract: According to Grothendieck’s definition, which is by now standard in part of the literature, an epimorphism is a map f: A → B such that for any maps g: B → C, h: B → C, if g ≠ h, then gf ≠ hf. In groups, for example, epimorphisms are onto, but in rings, for example, they are not.
158 citations
150 citations
TL;DR: The prolonged release of TSH which occurred after stat injection of 400 μg TRH to the patients with greatly diminished renal function was similar to that found after a 4-hr infusion of 1600 μg in normal men.
Abstract: Thyrotropin-releasing hormone (TRH) was administered iv to 8 patients with renal failure, 8 normal men, and 5 children. Injection of 1600 μg TRH as a bolus to healthy adults or a smaller dose to children resulted in a normal pattern of TSH release. The prolonged release of TSH which occurred after stat injection of 400 μg TRH to the patients with greatly diminished renal function was similar to that found after a 4-hr infusion of 1600 μg in normal men. In the men receiving the iv infusion, TSH levels began to diminish after 2 hr, despite the continued infusion of TRH for an additional 2 hr. An unexpected increase of hGH was also found in 7 of 8 patients with renal failure after injection of TRH.
133 citations
01 Feb 1973
TL;DR: In this paper, the mass, volume, center of mass and mass moment of inertia of the head and neck and the head were determined for twenty human male cadavers by external measurements and by use of x-ray procedures.
Abstract: : The mass, volume, center of mass and mass moment of inertia of the head and neck and the head were determined for twenty human male cadavers. Anthropometric values and anatomic landmarks were obtained by external measurements and by use of x-ray procedures. The procedures used to determine the above measurements are described. Uniform planes for the separation of the head and neck from the torso and separation of the head from the neck were established and are described in detail. The values of the physical properties of the head and neck and the head are tabulated and compared to data reported in previous studies.
130 citations
TL;DR: Stimulation of LH release induced by LH-RH was not potentiated by the smaller doses of estrogens, and stimulation of LH released by the more powerful estradiol-E in doses of 0.5-25 μg/ml lowered the basal release of LH and FSH, and inhibited the response to RH, FSH release being much more susceptible to this inhibitory effect than LH release.
Abstract: The effects of 17β-estradiol (E), ethinylestradiol (EE), progesterone (P), 5α-dihydroprogesterone (5DHP), 17α-hydroxyprogesterone (17HP), testosterone (T), dihydrotestosterone (DHT) and combinations of P, 5DHP, 17HP with E on the basal release of LH and FSH, as well on the pituitary responses to synthetic LH and FSH-releasing hormone (LH-RH/ FSH-RH), were examined in vitro using isolated rat pituitaries. EE in doses of O.OOO16-O.5 μg/ml suppressed release of LH and FSH in response to LH-RH. E in doses of 0.036-0.08 μg/ml augmented the basal level of LH in the medium and rarely that of FSH, but inhibited the release of FSH in response to LH-RH. Stimulation of LH release induced by LH-RH was not potentiated by the smaller doses of estrogens. E in doses of 0.5-25 μg/ml lowered the basal release of LH and FSH, and inhibited the response to LH-RH, FSH release being much more susceptible to this inhibitory effect than LH release. P in doses of 1.1-10 μg/ml did not affect basal release of LH and FSH and a dose o...
113 citations
111 citations
TL;DR: A simple technique is presented for rapid screening of leukocytes of patients suspected of having a defective intracellular mechanism for the bactericidal and digestive disposal of bacteria.
Abstract: A simple technique is presented for rapid screening of leukocytes of patients suspected of having a defective intracellular mechanism for the bactericidal and digestive disposal of bacteria.
110 citations
TL;DR: The results explain why β-hexosaminidase A has been previously reported by other investigators to hydrolyze Gm2 only with great difficulty and relate the inordinate storage of GM2 to the absence of β- hexosaminidsase A in the classical form of Tay-Sachs disease.
TL;DR: The rostral projections of the fastigial nucleus demonstrated by anatomic technics for the first time in this study correspond with those previously demonstrated by electrically evoked potentials.
TL;DR: Synthetic 3H-labeled luteinizing hormone-releasing hormone (LH-RH) with a specific activity of 18.3 Ci/mM and the same biological activity as pure porcine LH-RH was used to study the half-life, metabolism and urinary excretion of LH- RH in man.
Abstract: Synthetic 3H-labeled luteinizing hormone-releasing hormone (LH-RH) with a specific activity of 18.3 Ci/mM and the same biological activity as pure porcine LH-RH was used to study the half-life, metabolism and urinary excretion of LH-RH in man. Seven healthy men were given a rapid iv injection of 42 μCi of 3H-LH-RH, followed in 6 of the subjects by 250 μg unlabeled LH-RH. Frequent samples of blood and urine were collected. There was a mean maximum increase in plasma levels of LH of 963% and FSH of 312% in samples obtained 30 min after injection. A plot of the disappearance times in the plasma was characteristic of a multiexponential curve. The half-life of the first exponential curve, which probably represents the half-life of LH-RH in man, was 4 min and for the second curve was 57 min. The distribution volume, when expressed as a percentage of body weight was 8.7%. One hr after the injection of the labeled LH-RH, 48.2 ± 5.4% of the dose of radioactivity was found in the urine and after 24 hr 73.5...
TL;DR: The data were interpreted to suggest that MSH and MRIH-I affects attentional processes more profoundly in visually deficient animals.
TL;DR: It was concluded that hormonal fluctuation rather than intrinsic neural rhythmicity was the major determinant of estrous running periodicity in the rat.
TL;DR: The GH-RIF tetradecapeptide, prepared by the cyclization of a linear, disulfhydryl peptide intermediate by treatment with potassium ferricyanide, inhibited the secretion of radioimmunoassayable growth hormone in vitro at doses as low as 0.1 μg.
TL;DR: Bilateral ablation of the eystalks of the lobster results in the acceleration of proecdysial preparations and precocious initiation of ecdysis and α-Ecdysone was ineffective in inducing proecdysis and shortening the molt cycle in fifth stage lobsters when injected during early postECDysial stages.
TL;DR: The results demonstrate that pulmonary vascular resistance can be increased at stimulus frequencies in the physiological range of discharge for the sympathetic nervous system.
Abstract: The effect of sympathetic nerve stimulation on the pulmonary circulation was studied in a hemodynamically separated dog lung in which blood flow was maintained constant with a pump. Electrical stimulation of the stellate ganglia at 3, 10, and 30 cps produced a significant increase in mean lobar arterial perfusion pressure. Since lobar blood flow and left atrial pressure did not change during nerve excitation, the increase in lobar arterial pressure reflected an increase in vascular resistance across the lung. The increase in pulmonary vascular resistance was dependent on the stimulus frequency, and the time from the onset of stimulation to the attainment of the peak response was inversely related to the stimulus frequency. The response to nerve stimulation was decreased by alpha-receptor blocking agents. Lobar perfusion with a roller pump had an effect similar to perfusion with a piston pump. The response to nerve stimulation was independent of changes in rate, rhythm, and volume of respiration, changes in aortic blood pressure, and changes in airway resistance. The effects of stellate stimulation and of injected norepinephrine on vascular resistance were similar in the hemodynamically separated lobe. In essence, sympathetic nerve stimulation produced an active increase in vascular resistance in the pulmonary circulation, and the contribution of passive factors such as changes in respiration, bronchomotor tone, and bronchial circulation was minimal. Since the response was blocked by phentolamine, the increase in pulmonary vascular resistance in response to nerve stimulation was attributed to activation of alpha receptors in the pulmonary vascular bed by neurally released norepinephrine. These results demonstrate that pulmonary vascular resistance can be increased at stimulus frequencies in the physiological range of discharge for the sympathetic nervous system.
TL;DR: Investigation was made to determine whether high blood pressure (hypertension) could be lowered thru muscular relaxation and hypnosis, and significant lowering of both systolic and diastolic pressures was obtained.
Abstract: Investigation was made to determine whether high blood pressure (hypertension) could be lowered thru (a) muscular relaxation and (b) hypnosis. Six non-medicated hypertensive patients were used as controls while another six served as treatment Ss receiving muscular relaxation and hypnosis procedures. Nine patients on stabilized anti-hypertensive medication also received the muscular relaxation and hypnosis procedures. Significant lowering of both systolic and diastolic pressures was obtained in both the no drug and drug groups receiving treatment, but there was no significant reduction in the control group. Hypertensive levels were reduced thru muscular relaxation and completely eliminated during hypnosis. Instruction was given in self-relaxation and self-hypnosis to promote continuation of beneficial effects beyond hospitalization.
TL;DR: In this article, the authors found that after OCB section and degeneration, there was a significant decrease in Choline acetyltransferase (ChAc) activity in the right cranial nerve.
Abstract: — Choline acetyltransferase (ChAc; EC 2.3.1.6) was assayed in the membranous cochlea and in the eighth cranial nerve (both the vestibular and cochlear components) from the point where it leaves the brain stem to the internal auditory meatus of the cat. To determine the contribution of the efferent innervation of the cochlea to this enzymatic activity both eighth nerves and both membranous cochleae were assayed at 17–29 days following section of the right, crossed and uncrossed olivo-cochlear bundles (OCB) in the cat. The lesion was produced along the right sulcus limitans on the floor of the fourth ventricle. The left eighth nerves and cochleae served as controls in the ChAc assay. There was a significant decrease in ChAc activity in the right cochlea and eighth nerve after OCB section and degeneration. The mean activity of ChAc in the right cochleae of the 6 operated cats was 15 ± 7 μg of ACh formed. h−1 (g wet wt. of tissue) −1 in comparison to the rate of all the intact cochleae of 156 ± 38 μg of ACh formed. h−1. (g of tissue)−1, a statistically significant difference (P < 0005). The mean activity of ChAc in the right eighth nerves of the cats with OCB lesions was 30 ± 8 n-g of ACh formed. h−1. (g of tissue)−1in comparison to 91 ± 19 fig of ACh formed . h−1. (g of tissue)−1 found for intact eighth nerves. This difference was also significant (P < 0005). Thus, section and degeneration of the crossed and uncrossed OCB reduce the activity of ChAc in the eighth nerve and membranous cochlea. This finding provides support for the hypothesis suggesting the cholinergic nature of olivo-cochlear transmission.
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01 Jun 1973TL;DR: The conclusion is reached that in mammals MSH exhibits definite extra-pigmentary actions upon behavior and is speculated that during the course of evolution, MSH has maintained its “adaptive” value for the organism, but that this may apply only to simple tasks.
Abstract: Publisher Summary This chapter explores the behavioral aspects of melanocyte-stimulating hormone (MSH). The pituitary hormone MSH is tested in several different behavioral systems. MSH is a hormone(s) whose presence has persisted in the pituitary gland of vertebrates from very low forms to man. The primary function of MSH in higher mammals no longer seems to be pigmentary, but this is not sufficient reason to assume that MSH has no role in mammals or that the effects of MSH can be ascribed to corticotrophin (ACTH). Although MSH is known to play a vital role in amphibians such as the frog, an important function for MSH in mammals such as the rat is not well recognized. The frog better adapts to the environment by changing the color of its skin, an effect mediated by MSH. Extra-pigmentary effects of MSH upon bodily processes other than the central nervous system (CNS) are described by several investigators, including ourselves. It is speculated that during the course of evolution, MSH has maintained its “adaptive” value for the organism, but that this may apply only to simple tasks. The conclusion is reached that in mammals MSH exhibits definite extra-pigmentary actions upon behavior.
TL;DR: The most compelling indirect evidence has been obtained which supportes the hypothesis that TRH may be a physiological regulator of both TSH and PRL, and may more precisely indicate the biological activities of pGlu-His-ProNH 2 in man.
TL;DR: The elevated tissue to plasma ratio in the Pineal, along with the identification of unchanged H-Pro-Leu-Gly-NH2 there, suggests the possibility of a direct influence of the hypothalamus upon the pineal gland.
Abstract: H-Pro-Leu-Gly-NH2, a potentinhibitor of melanocyte stimulating hormone (MSH) release [MSH-release inhibiting factor (MIF)], was labeled with 14C-leucine or 3H-proline and injected i.v. into rats. H-Pro-14C-Leu-Gly-NH2 was found to have a half-life of approximately 9 min and to be distributed in a space greater than that of the plasma volume. Relatively little radioactivity and no intact H-Pro-Leu-Gly-NH2 could be found in the urine 1 h after administration. 3H- and 14C-labeled-H-Pro-Leu-Gly-NH2 accumulated in the pineal, pituitary, kidney, liver, and adrenals; the elevated tissue to plasma ratio in the pineal, along with the identification of unchanged H-Pro-Leu-Gly-NH2 there, suggests the possibility of a direct influence of the hypothalamus upon the pineal gland.
TL;DR: An astrocytic lineage is proposed in which glioblasts present in the lateral funiculus of the cervical spinal cord give rise to astroblasts that then develop into matureastrocytes that are in direct continuity with developing myelin.
Abstract: An electron-microscopic study has been made of the glial cells in the developing lateral funiculus of the cervical spinal cord in fetal rhesus monkeys. The various macroglial cell types, their precursor cells, and microglia are discussed in detail. An astrocytic lineage is proposed in which glioblasts present in the lateral funiculus give rise to astroblasts that then develop into mature astrocytes. Oligoblasts apparently migrate into the lateral funiculus as such and develop into active oligocytes. The active oligocytes become most predominant during the initial stages of myelinogenesis and are in direct continuity with developing myelin. The active oligocytes develop into mature oligocytes after myelination is completed. Microglia cells are present throughout development as three forms; resting microglia, globose microglia, and active microglia. The globose and active microglia predominates at specific times early in development when degeneration of apparent neuronal processes is taking place. The microglia cells are characterized by dense nuclear chromatin clumps, lipid inclusion bodies, dense vesicles, and, often, intracellular debris.
TL;DR: The distribution of colloidal iron binding sites coincides with those for the carbohydrate-complexing phytohemmagglutnin, concanavalin A, which suggests that these membrane-fixed anions are acid mucopolysaccharides, glycoproteins or glycolipids.
TL;DR: To appreciate the environmental distribution of endotoxins, studies were undertaken to compare the Gram negative endotoxin content of New Orleans water with that of other cities, as well as endotoxin distribution in various beverages and biological fluids.
Abstract: DURING an evaluation of the Limulus lysate assay procedure1–6 for the detection of Gram negative endotoxins, deionized water was found to be contaminated with endotoxins. Endotoxins were also present in samples of New Orleans tap water, which comes from deep levels of the Mississippi River. To appreciate the environmental distribution of endotoxins, studies were undertaken to compare the Gram negative endotoxin content of New Orleans water with that of other cities, as well as endotoxin distribution in various beverages and biological fluids.
TL;DR: Two methods of isolating mutants of Aspergillus in which aflatoxin production is attenuated or lost are presented and mutants are selected on the basis of altered fluorescence under ultraviolet light.
Abstract: Mutations affecting the production of aflatoxin might be useful in studying its biosynthesis, and in understanding the wide variation in aflatoxigenicity of fungal strains isolated from nature. Two methods of isolating mutants of Aspergillus in which aflatoxin production is attenuated or lost are presented. In one method mutants are selected on the basis of altered fluorescence under ultraviolet light. The second method utilizes a mutant strain which produces aflatoxin and an orange-red mycelial pigment not detected in the wild type. Unpigmented mutants derived from this strain exhibit lowered or lost aflatoxigenicity.
TL;DR: Rare benign neoplasms occur which are composed solely of Leydig cells derived from ovarian stroma rather than from preexisting hilus cells of the mesovarium, and similar tumors lacking crystalloids, in the absence of definitive diagnostic criteria are best classified as lutein cell tumors.
Abstract: Rare benign neoplasms occur which are composed solely of Leydig cells derived from ovarian stroma rather than from preexisting hilus cells of the mesovarium. Two such tumors are described and two are noted in the literature although others, difficult to identify, undoubtedly exist. They are closely related to the stromal-Leydig cell tumor but are not multifocaland lack the thecoma-like stromal component. Both types of neoplasm occur in menopausal or post-menopausal women and are likely to be associated with masculinization. They are related to each other as the stromal luteoma is related to the partly luteinized theca cell tumor. The presence of crystalloids of Reinke in some of the lipid cells identifies the lipid cell component of the tumor as Leydig cells. Similar tumors lacking crystalloids, in fact, may be Leydig cell tumors but in the absence of definitive diagnostic criteria are best classified as lutein cell tumors.