Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UNIPROT:P61278 (somatostatin)
 22,083 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Hypothalamic growth hormone-releasing hormone (GHRH) and somatotropin release-inhibiting factor or somatostatin (SS) immunoreactive (ir) neurons were localized in pigs (n = 8) and cattle (n = 7) to identify neuroanatomical sites involved in the regulation of growth hormone secretion. Coronal and sagittal frozen sections (30-60 microns) of Zamboni's fixed hypothalamic tissue, without prior colchicine treatment were incubated with GHRH or SS primary antisera for 48 h, then visualized by peroxidase-diaminobenzidine immunocytochemistry. Fusiform, bipolar SS-ir perikarya were located about the third ventricle in the periventricular nucleus, extending from rostral aspects of preoptic periventricular nucleus to a level approximate with caudal regions of the paraventricular nucleus. Rounded or fusiform, bipolar GHRH-ir perikarya were mostly located in ventrolateral portions of the arcuate nucleus in pigs and cattle, and within ventral aspects of the ventromedial nucleus in pigs but rarely in cattle. In both pigs and cattle, SS-ir and GHRH-ir fibers projected ventrally into the median eminence with dense and overlapping innervation of the external layer, especially dense in lateral regions. In pigs, but not as distinguishable in cattle, SS-ir fibers also densely innervated the ventromedial and arcuate hypothalamic nuclei. Double immunostained sections revealed close apposition of SS-ir fibers and varicosities with GHRH-ir perikarya in arcuate and ventromedial nuclei, and apposition of SS-ir and GHRH-ir varicosities in the median eminence.
 ...
PMID:Growth hormone-releasing hormone and somatostatin neurons within the porcine and bovine hypothalamus. 790 43

The neuronal expression of the protooncogene c-fos may serve as a marker of neural activity. We previously examined brain sites upon which GH exerts an immediate early influence in rats and determined that the c-fos gene was transiently expressed in the hypothalamic periventricular nucleus (PeV) and arcuate nucleus (ARC) after recombinant human GH (rhGH) administration. As the distribution of c-fos messenger RNA (mRNA)-containing cells appeared to overlap with that of somatostatin (SS) neurons in both the PeV and ARC, we hypothesized that GH exerts a feedback effect on hypothalamic SS neurons. To extend this hypothesis, we characterized the neurons expressing the c-fos gene in response to rhGH administration in hypophysectomized rats. Adult male Wistar rats were hypophysectomized 10 days before use. After hypophysectomy, rats received daily sc injections of cortisone acetate (0.5 mg/kg BW) and L-T4 (20 micrograms/kg BW). Four international units (1.33 mg) of rhGH were given iv through an indwelling right atrial cannula. The vehicle was given to the control animals. Coronal sections of the hypothalamus were processed for in situ hybridization after rhGH or vehicle administration. To estimate the localization of neurons expressing the c-fos gene, the adjacent hypothalamic sections, 30 microns in thickness, were processed for hybridization histochemistry for SS, neuropeptide-Y (NPY), or GRF mRNA. In the ARC, the distribution of c-fos mRNA-containing cells appeared to overlap with that of NPY and partially with that of SS mRNA-containing cells, but it clearly differed from the distribution of GRF mRNA-containing cells. In the PeV, distribution of the cells expressing the c-fos gene was comparable to that of SS mRNA-containing cells. To further ascertain the distribution, hypothalamic sections, 6 microns in thickness, were processed by double label in situ hybridization using a 35S-labeled c-fos cRNA probe and a digoxigenin-labeled NPY or SS cRNA probe. In the ARC, 65% of the c-fos gene-expressing cells were NPY neurons. In the PeV, 60% of the c-fos gene-expressing cells were SS neurons. NPY is known to act within the hypothalamus and inhibit GH secretion via SS in rats, and the NPY neurons in the ARC have been shown to project to SS neurons in the PeV. Our findings suggest that the feedback effect of GH on the hypothalamus is mediated not only by SS neurons in the PeV, but also by NPY neurons in the ARC.
 ...
PMID:Growth hormone induces expression of the c-fos gene on hypothalamic neuropeptide-Y and somatostatin neurons in hypophysectomized rats. 798 69

Seasonal changes in daylength (photoperiod) affect many aspects of mammalian physiology and behavior, including reproduction, metabolism, thermoregulation, and sleep. The circadian pacemaker in the hypothalamic suprachiasmatic nuclei (SCN) regulates these photoperiodic changes. Our studies of the Siberian hamster SCN have shown that two types of neuropeptide-containing neurons, vasopressin (AVP) and vasoactive intestinal peptide (VIP) neurons, respond to short photoperiod by decreasing mRNA expression. The present studies investigated whether photoperiodic inhibition of mRNA expression also occurs in somatostatin-synthesizing neurons in the SCN, depends upon the pineal gland, and occurs in neurons in other hypothalamic nuclei. Juvenile Siberian hamsters exposed to either long photoperiod (16 h light/day) or short photoperiod (10 h light/day) for 2 weeks after weaning, were used for these studies. Coronal sections throughout the SCN were prepared and processed for in situ hybridization. The results showed that photoperiod decreased the expression of AVP mRNA and VIP mRNA in the SCN, as seen previously, but not somatostatin mRNA. Furthermore, pinealectomy did not attenuate the short photoperiod inhibition of AVP mRNA and VIP mRNA expression in the SCN. Also, short photoperiod inhibition of AVP mRNA expression was found in the paraventricular and supraoptic nuclei, as well as in the SCN. These results show that short photoperiod inhibition of mRNA expression is partially selective among the neuropeptides, but is not restricted to the SCN. Furthermore, these findings suggest that photoperiodic regulation of neuropeptide mRNA expression is independent of pineal melatonin secretion and gonadal steroid secretion.
 ...
PMID:Photoperiodic regulation of hypothalamic neuropeptide messenger RNA expression: effect of pinealectomy and neuroanatomical location. 963 May 80

Previously, we demonstrated that systemic injection of the growth hormone secretagogue, growth hormone-releasing peptide (GHRP)-6, selectively activated cells in the hypothalamic arcuate nucleus, as reflected by increased electrical activity and induction of the immediate early gene c-fos. The growth hormone secretagogue receptor distribution is not confined to the arcuate nucleus, suggesting that additional sites of action may exist. In the present study we characterized the electrophysiological responses of cells in the arcuate nucleus, ventromedial nucleus and periventricular nucleus in an in-vitro hypothalamic slice preparation, following bath application of GHRP-6. Additionally, since central somatostatin administration has been shown to attenuate the induction of the c-fos gene by GHRP-6, we sought to determine whether the arcuate cells activated by GHRP-6 are also somatostatin-sensitive. Male Wistar rats (100-150 g body weight (BW)) were anaesthetized (urethane; 1.2 g/kg BW) and the brains removed. Coronal sections (400 microm thickness) were cut through a block of hypothalamus and were transferred to a slice chamber perfused with artificial cerebrospinal fluid. Forty-one arcuate nucleus cells were tested with bath application of 15 microm GHRP-6 for 10 min, 16 of which were tested subsequently (>30 min later) with application of 10 microM somatostatin. Following GHRP-6 administration, 19 cells (46. 3%) showed a significant increase in firing rate during the 15-min period after GHRP-6 application (P<0.001), 17 cells (41.5%) did not respond and the remaining five cells (12.2%) were significantly inhibited. Six of the eight arcuate nucleus cells that were excited by GHRP-6 were significantly inhibited by somatostatin. By contrast, five of the six arcuate nucleus cells that were unresponsive to GHRP-6 were also unresponsive to somatostatin. In the ventromedial nucleus, of 19 cells tested, eight cells (42.1%) were excited by GHRP-6, eight cells (42.1%) were unresponsive and the remaining three cells (15.8%) were significantly inhibited. Of 19 cells recorded in the periventricular nucleus, 13 (68.4%) were unresponsive to GHRP-6 and six (31.6%) were significantly inhibited. Thus, electrophysiological studies in vitro suggest that: (1) neurones in the hypothalamic arcuate nucleus, ventromedial nucleus and periventricular nucleus show changes in electrical activity in response to GHRP-6; and (2) the arcuate nucleus cells excited by GHRP-6 are also subject to inhibitory control by somatostatin.
 ...
PMID:GHRP-6-induced changes in electrical activity of single cells in the arcuate, ventromedial and periventricular nucleus neurones [correction of nuclei] of a hypothalamic slice preparation in vitro. 1058 26

The mammalian superior colliculus is an important subcortical integrator of sensorimotor behaviours. It is multi-layered, each layer containing specific neuronal types and possessing distinct input/output relationships. Here we use in situ hybridisation methods to map the distribution of seven neurotransmitters/neuromodulator systems in adult rat superior colliculus. Coronal sections were probed for preprotachykinin, cholecystokinin, somatostatin, proenkephalin, neuropeptide Y and the enzymes glutamic acid decarboxylase and choline acetyltransferase, markers for GABA and acetylcholine respectively. Cells expressing glutamic acid decarboxylase messenger RNA were the most abundant, the highest density being found in the superficial layers. Many cells containing proprotachykinin messenger RNA were found in stratum zonale and the upper two-thirds of stratum griseum superficiale; cells were also located in deeper tectal laminae, particularly caudomedially. Most cholecystokinin messenger RNA expressing cells were located in the superficial layers with a prominent band in the middle third of stratum griseum superficiale. Cells expressing moderate to high levels of somatostatin messenger RNA formed a dense band in the lower third of stratum griseum superficiale/upper stratum opticum; two less distinct tiers of labelling were seen in deeper layers. These in situ hybridisation data reveal three distinct sub-laminae in rat stratum griseum superficiale. Cells expressing moderate to low levels of proenkephalin messenger RNA were located in lower stratum griseum superficiale/upper stratum opticum and intermediate laminae. A cluster of enkephalinergic cells was located medially in the deep tectal laminae. Expression of neuropeptide Y messenger RNA was relatively low and mostly confined to cells in stratum griseum superficiale and stratum opticum. No choline acetyltransferase messenger RNA was detected. This in situ analysis of seven different neurotransmitters/neuromodulator systems sheds new light on the neurochemical organisation of the rat superior colliculus. The data are related to what is known anatomically and physiologically about intrinsic and extrinsic tectal circuitry, and the potential involvement of different neuropeptides in these circuits is discussed. The work forms the basis for future developmental studies examining the effects of transplantation and visual deprivation/deafferentation on tectal neurochemistry and function.
 ...
PMID:Expression of messenger RNAs for glutamic acid decarboxylase, preprotachykinin, cholecystokinin, somatostatin, proenkephalin and neuropeptide Y in the adult rat superior colliculus. 1124 59

West syndrome, an age-specific epileptic encephalopathy, manifests with infantile spasms (IS) and impaired neurodevelopmental outcomes and epilepsy. The multiple-hit rat model of IS is a chronic model of IS due to structural etiology, in which spasms respond partially to vigabatrin analogs. Using this model, we investigated whether IS due to structural etiology may have deficits in parvalbumin (PRV) and somatostatin (SST) immunoreactive (-ir) interneurons, and calretinin-ir (CR-ir) neurons of the primary somatosensory cortex of postnatal day (PN) 20-24 rats, using specific immunohistochemical assays. PN3 Sprague-Dawley male rats underwent the multiple-hit induction protocol, were monitored until PN20-24, and were transcardially perfused to collect brains for histology. Age-matched sham and naive control male rats were also used. Coronal brain cryosections were stained with anti-PRV, anti-CR, and anti-SST antibodies, and regions of interest (ROIs) from the primary somatosensory cortices were selected to determine PRV-, CR-, and SST-ir cell counts and cortical ROI volumes, with blinding to experimental group. Statistical analyses were done using a linear mixed model accounting for repeated measures. We found PRV-ir interneuronal selective reduction, sparing of the CR-ir and SST-ir neurons, and bilateral cortical atrophy. Our findings provide evidence for acquired PRV-selective interneuronopathy, possibly underlying the pathogenesis of IS, neurodevelopmental deficits, and epilepsy, and potentially contributing to the partial response to vigabatrin analogs in this model.
 ...
PMID:Acquired parvalbumin-selective interneuronopathy in the multiple-hit model of infantile spasms: A putative basis for the partial responsiveness to vigabatrin analogs? 3056 74