Showing papers in "General and Comparative Endocrinology in 1970"

TL;DR: The evidence attests to the possibility that the pineal organ of at least some fishes is involved in the mediation of the gonadal changes effected by changing photoperiods, as well as suggesting a possible mode of action of the melatonin.

TL;DR: A stereotaxic method for placement of electrodes in the goldfish hypothalamus was described in this paper, which provided direct evidence for hypothalamic control of thyroid gland activity in goldfish.

TL;DR: The conversion of α- to β-ecdysone occurs efficiently in isolated abdomens of Calliphora and Bombyx, thus indicating that the ecdysial gland may not be the site of this conversion, and that the observed hormonal effect of β-ECDysone may be due in part to its prior metabolism to α-ecdYSone.

TL;DR: Regulation of the inorganic constituents of the serum is nearly perfect in hypophysectomized Fundulus heteroclitus maintained in salt water, although serum Cl is lower and serum inorganic PO4 and serum Mg increased.

TL;DR: It was concluded that inspection for wounds after chronic grouping provided a better index of relative aggressiveness for this type of experiment than did the more traditional short daily observations of paired animals.

TL;DR: The abundance of lipid, in contrast to the sparse glycogen deposits, in both dogfish and ratfish liver (70% and 80% of wet weight), implies that lipid reserves may be of more fundamental physiologic importance to these fishes.

TL;DR: Results clearly show that the atretio follicle of the Guppy does not produce steroid hormones, and it is preferable to use the name Corpus atreticum instead of Corpus luteum praeovulationis.

TL;DR: A very low dose (0.1 μg) of a purified FSH from Papkoff was found to promote ovarian development, oviducal enlargement, and ovulation in the hypophysectomized lizard.

TL;DR: The glandular lobe of the corpus cardiacum in L. migratoria is more potent than the storage lobe in elevating the active phosphorylase levels in the fat body, and the changes in the specific activity of the total phosphoryLase are independent of the factors from the corpora cardiaca.

TL;DR: L'abaissement des concentrations plasmatiques d'electrolytes consecutif a l'ablation de l'hypophyse provient donc specifiquement du desequilibre des echanges ioniques et non d'une augmentation de the permeabilitea l'eau.

TL;DR: Aldosterone and corticosterone levels in cockerels were measured by the double isotope derivative assay in intact and surgically stressed animals as discussed by the authors, and the results indicated that the pituitary plays a role in maintaining the adrenal secretion of aldosterone.

TL;DR: A sensitive, specific bioassay, based on the dermal melanophore response of larval amphibians, for the quantitative estimate of melatonin is presented.

TL;DR: The results of the immunochemical approach have shown a general correlation with evolutionary development and was more reliable in this regard than the biological approach.

TL;DR: A review of the literature of the action of hormones on insect tissues in vitro published between 1915 and 1970 indicates that research has been concerned with four main areas: studies of the development of imaginal discs, studies of morphogenesis and cuticle secretion in epidermal tissues, Studies of theDevelopment of gonads, and studies of secretory activity in endocrine glands.

TL;DR: In vitro steroid biosynthesis in the 700 g supernatant fraction of the male-phase ovotestis of Ariolimax californicus was investigated and it was shown that the following sequence occurred in male- phases: Cholesterol → pregnenolone → 17a-hydroxypregnenolones → dehydroepiandrosterone → androstenedione.

TL;DR: An intravenous infusion of l -arginine resulted in a prompt and significant increase in plasma growth hormone (GH) in sheep and cows but not in pigs, and the insulin secretory response of pigs, although statistically significant, was considerably less than that seen in the two ruminant species studies.

TL;DR: In 18 experiments involving 43 incubations with acidic hypothalamic extracts the rate of gonadotropin release from chicken pituitaries was significantly greater than with cortical extracts on 37 occasions, and overall the mean increase in rate was highly significantly different.

TL;DR: Specimens of two species of Mugil were collected from three environments differing in salinity (freshwater, seawater, and a hypersaline lagoon) and volumetric and histological changes in the proximal and rostral pars distalis of pituitaries from these fish are described.

TL;DR: The changes seen in the pituitary reflect cycles of activity related to the maturation of ova and to the presence of a gestation cycle, and a model for the control of the gonadotropic cells is proposed.

TL;DR: It is concluded that the seasonal ambisexual character here investigated, the height of the tail, is prolactin dependent, and the parallelism between water drive and tail height variations is stressed.

TL;DR: Ces differents resultats concernant the regulation endocrine de l'hemogramme permettent de comprendre les variations normales que nous observons au cours du developpement de Locusta migratoria.

TL;DR: Gonadotropic and TSH cells were both spontaneously active in organ culture and a model for their control proposed and the identity of the TSH and gonadotropic cells was confirmed.

TL;DR: Pathways leading from pregnenolone to androstenedione (the delta-4, and the delta-5 pathways) similar to those operating in the mammalian ovary, have been demonstrated to operate in the ovary of Tilapia.

TL;DR: The results obtained demonstrate the presence of 11-hydroxylase activity in the ovary of the mullet and show that ecological differences may influence steroidogenesis in the Ovary ofThe mullet.

TL;DR: Prolactin-thyroid antagonism appears to be a general phenomenon in Amphibia and animals showed metamorphic stasis while the TSH controls completed metamorphosis.

TL;DR: The steroid-synthetic capacity of the mature testis of the teleost Gobius paganellus was studied in vitro by incubating the tissue with pregnenolone-4-14C of four different specific activities for four different time intervals.

TL;DR: Despite its relatively advanced status at the holostean organizational level, Amia reveals a remarkably developed median eminence in comparison with fishes considered to be more primitive, as observed by light and electron microscopy.

TL;DR: Based on changes in ultrastructure and vasotocin content, two postoperative phases can be distinguished in the neural lobes disconnected from the hypothalamus as mentioned in this paper, where the axons filled with tubular formations are more numerous than in the controls.

TL;DR: Each active peak is effective on all four pigmentary effectors, causing light-adaptation of distal retinal pigment and dispersing the pigments in melanophore, leucophores, and erythrophores.

TL;DR: These experiments indicate that in slowly maturing female desert locusts, low rates of oocyte development are accompanied by a slow turnover of neurosecretory material, with synthesis exceeding release, resulting in the accumulation of neurosecretion within the corpora cardiaca.