Nikki McArthur

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Mammalian ovaries contain sympathetic neurons expressing the low affinity neurotropin receptor (p75NTR). To date neither the role these neurons might play in ovarian physiology nor their embryological origin is known. Immunohistochemistry was used to detect postnatal changes in distribution and number of both p75NTR-positive and tyrosine(More)
A study was undertaken to further the understanding of the mechanism by which suckling inhibits the release of pituitary LH and depresses the postovariectomy rise of plasma LH in lactating mammals. To that end, the effect of suckling (10 pups/animal) for 1 or 3 weeks on the LHRH content of the hypothalamus and preoptic area (POA) in ovariectomized and(More)
Enzyme activity and fine structure of thyroid follicular cells were investigated in domestic cats at ages: 2 and 8 months, and 1, 3, 5 and 8 years. The following major changes in the follicular cells with advancing age were observed: with histochemistry--an increase in acid phosphatase and beta-glucuronidase activities confined to numerous granules(More)
The ependymal and supraependymal cells of the armadillo infundibulum (INF) were investigated by correlative histochemistry, scanning and transmission electron microscopy. Eighteen armadillos (8 adult females, 6 adult males, 2 immature females and 2 immature males) were examined. The following supraependymal elements were observed: (a) individual(More)
Magnetic resonance imaging (MRI) was performed on the brain of 5 normal, anesthetized, neonatal (age 3-to-6 days) Quarter Horse foals. The objectives of the study were to develop a technique for imaging the brain of neonatal foals, and to ascertain their normal brain anatomy. Intravenous propofol was administered for induction and maintenance of general(More)
The distribution of gonadotropin-releasing hormone (GnRH) was studied in the brain and infundibulum (INF) or median eminence of sheep utilizing a peroxidase-antiperoxidase immunohistochemical method. This procedure utilized a specific antiserum generated against GnRH conjugated to bovine serum albumin. In the rostral INF, the greatest concentration of GnRH(More)
Neural structures containing gonadotropin-releasing hormone (GnRH) in the bovine brain and infundibulum were characterized by light microscopic immunohistochemistry. GnRH-positive perikarya were localized singly or in small groups within the infundibular nucleus and were seen grouped in large discrete clusters within the ventromedial nucleus. Positive axons(More)
Immunohistochemical localization of the decapeptide gonadotropin releasing hormone (GnRH) in neural structures in the pony brain and infundibulum (INF) was conducted at the light-microscopic level. This procedure utilized an antiserum generated against GnRH conjugated to bovine serum albumin. In the rostral INF, GnRH was distributed mainly in the external(More)
Suckling has been demonstrated to impair the release of pituitary luteinizing hormone (LH) and to prevent the dramatic increase in plasma LH observed following ovariectomy. In the present study, the effect of suckling (10 pups/animal) for either 1 or 3 weeks on the relative amount of luteinizing hormone releasing hormone (LHRH) present in the hypothalamus(More)
Mifepristone (RU486), bovine corticotropin-releasing hormone (CRH), arginine vasopressin (VP), adrenocorticotropin (ACTH1-24), and protein kinase activators (forskolin, [FSK]; phorbol 12-myristate 13-acetate [PMA]) were used in vitro to investigate their direct effect on adrenocorticosteroidogenesis. Bovine adrenocortical fasciculata/reticularis cells (2 x(More)