https://www.cell.com/trends/neurosciences/pdf/0166-2236(95)93946-U.pdf

Opioid-receptor mRNA expression in the rat CNS: anatomical and functional implications

The mu, delta, and kappa opioid receptors are the three main types of opioid receptors found in the central nervous system (CNS) and periphery These receptors and the peptides with which they interact are important in a number of physiological functions, including analgesia, respiration, and hormonal regulation This study examines the expression of mu, delta, and kappa receptor mRNAs in the rat brain and spinal cord using in situ hybridization techniques Tissue sections were hybridized with 35S-labeled cRNA probes to the rat mu (744-1,064 b), delta (304-1,287 b), and kappa (1,351-2,124 b) receptors Each mRNA demonstrates a distinct anatomical distribution that corresponds well to known receptor binding distributions Cells expressing mu receptor mRNA are localized in such regions as the olfactory bulb, caudate-putamen, nucleus accumbens, lateral and medial septum, diagonal band of Broca, bed nucleus of the stria terminalis, most thalamic nuclei, hippocampus, amygdala, medial preoptic area, superior and inferior colliculi, central gray, dorsal and median raphe, raphe magnus, locus coeruleus, parabrachial nucleus, pontine and medullary reticular nuclei, nucleus ambiguus, nucleus of the solitary tract, nucleus gracilis and cuneatus, dorsal motor nucleus of vagus, spinal cord, and dorsal root ganglia Cellular localization of delta receptor mRNA varied from mu or kappa, with expression in such regions as the olfactory bulb, allo- and neocortex, caudate-putamen, nucleus accumbens, olfactory tubercle, ventromedial hypothalamus, hippocampus, amygdala, red nucleus, pontine nuclei, reticulotegmental nucleus, motor and spinal trigeminal, linear nucleus of the medulla, lateral reticular nucleus, spinal cord, and dorsal root ganglia Cells expressing kappa receptor mRNA demonstrate a third pattern of expression, with cells localized in regions such as the claustrum, endopiriform nucleus, nucleus accumbens, olfactory tubercle, medial preoptic area, bed nucleus of the stria terminalis, amygdala, most hypothalamic nuclei, median eminence, infundibulum, substantia nigra, ventral tegmental area, raphe nuclei, paratrigeminal and spinal trigeminal, nucleus of the solitary tract, spinal cord, and dorsal root ganglia These findings are discussed in relation to the physiological functions associated with the opioid receptors

/pdf/mu-delta-and-kappa-opioid-receptor-mrna-expression-in-the-4jongq3aco.pdf

Mu, Delta, and Kappa Opioid Receptor mRNA Expression in the Rat CNS: An In Situ Hybridization Study

I. Introduction II. Effects of Estrogen on GnRH Neurons A. Sexual differentiation B. Biosynthesis of GnRH C. Biosynthesis of galanin D. Electrical activity of GnRH neurons E. GnRH secretion F. GnRH degradation G. Ultrastructural changes involving GnRH neurons H. Summary of estrogen’s influence on GnRH cells III. Brain Sites of Estrogen Influence on GnRH Neurons A. Sites of estrogen’s stimulatory sites B. Sites of estrogen’s inhibitory action C. Summary IV. Pathways for Estrogen Regulation of GnRH Neurons A. Direct regulation of GnRH neurons B. Estrogen-receptive neurons as intermediaries C. Glial cells as intermediaries D. Summary V. Model of Estrogen Action on GnRH Neurons VI. Concluding Remarks

Multimodal Influence of Estrogen upon Gonadotropin-Releasing Hormone Neurons

Immunohistochemical localization of the cloned μ opioid receptor in the rat CNS

μ-Opioid receptor mRNA expression in the rat CNS : comparison to μ-receptor binding

With the recent development of highly specific ligands for the µ, δ and Kopioid receptors it was of interest to define the effects of activation of each of these receptor types on LH and prolactin (PRL) secretion. The compounds were infused (10 µl/h) at various concentrations into the third cerebroventricle of unanesthetized, ovariectomized rats. The µ agonist, DAGO, at both 1 and 10 µg/h caused a significant suppression of LH secretion and a significant stimulation of PRL release. DPDPE, the δ agonist, had no effect on either hormone at 1 µg/h but inhibited LH secretion at 10 µg/h. There was still no effect of this high dose of DPDPE on PRL release. The Kagonist, U50,488H, had no effect on either hormone at 10 µg/h, but at 100 µg/h produced a significant suppression of LH release and a highly variable increase in PRL. Coinfusion of 100 µg/h of naloxone with the high dose of each of the agonists completely blocked the responses of both hormones to each of the agonists with one exception: the highly variable stimulation of PRL by U50,488H was not affected, thus indicating a nonspecific effect of U50,488H on PRL secretion. These results demonstrate that: (1) activation of the µ receptors produces an inhibition of LH secretion and a stimulation of PRL release; (2) activation of the δ receptors produces an inhibition of LH secretion but has no effect on PRL release, and (3) activation of the Kreceptors produces an inhibition of LH release and a variable stimulation of PRL secretion.

Effects of specific activation of mu-, delta- and kappa-opioid receptors on the secretion of luteinizing hormone and prolactin in the ovariectomized rat.

Simona V. Yagenova

Papers

Effects of specific activation of mu-, delta- and kappa-opioid receptors on the secretion of luteinizing hormone and prolactin in the ovariectomized rat.