A N Hirshfield

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Nerve growth factor (NGF) epitomizes a family of proteins known as the neurotrophins (NTs), which are required for the survival and differentiation of neurons within both the central and peripheral nervous system. Synthesis of NGF in tissues innervated by the peripheral nervous system is consistent with its function as a target-derived trophic factor.(More)
An emerging body of evidence suggests that neurotrophins not only promote neuronal survival and differentiation, but can also target nonneuronal cells for their actions. Neurotrophins initiate their biological effects by binding to cell membrane tyrosine kinase receptors of the trk protooncogene family. In addition, all neurotrophins recognize with similar(More)
Recently, Gray and Ostby (Toxicol. Appl. Pharmacol. 133, 285-294, 1995) reported that in utero and lactational TCDD exposure causes striking abnormalities in the rat female reproductive system, including reduced fecundity and vaginal threads. The mechanism by which TCDD induces such abnormalities is unknown. Thus, we sought to determine: (1) whether TCDD(More)
In women, chronically elevated androgens have been associated with polycystic ovarian syndrome and infertility. Recently, we described transgenic mice with elevated serum LH secondary to targeted expression of a transgene encoding a chimeric LH beta-subunit. Mature transgenic females exhibit elevated androgens, anovulation, and a range of ovarian phenotypes(More)
The Caenorhabditis elegans death susceptibility gene, ced-3, has a number of homologs in vertebrate species, including interleukin-1 beta (IL-1 beta)-converting enzyme (ICE), Ich-1long, and CPP32. These genes, which encode a family of related proteases, have been shown to induce apoptosis when transfected into eukaryotic cells. However, it remains to be(More)
It is generally believed that in adult rodents the vast majority of very small follicles (less than 20 granulosa cells in cross section) are not growing. However, the only data to support this assumption were collected with methods that may not be sufficiently sensitive to distinguish between nongrowing follicles and slowly growing follicles. In this study,(More)
Little is known about the embryonic factors that regulate the size of the primordial follicle endowment at birth. A few studies suggest that members of the B-cell lymphoma/leukemia-2 (bcl-2) family of protooncogenes may be important determinants. Thus, the purpose of this study was to test whether bcl-2 regulates the size of the primordial follicle pool at(More)
Vasoactive intestinal peptide (VIP)-containing nerve fibers are present in ovarian follicles at all stages of development, and VIP, acting primarily via the cAMP pathway, has been reported to modulate many aspects of granulosa cell function. Herein we examined the effects of VIP and its potential mechanisms of action on apoptosis in antral follicles(More)
The purpose of this study was to characterize the patterns of ovarian cell proliferation during the earliest stages of folliculogenesis, which occur in the embryonic period and the first weeks postpartum in rats. Rats were given continuous infusions of [3H]thymidine (3H-TdR) or bromodeoxyuridine (BrdU), and cells that were synthesizing DNA were visualized(More)