Location, distribution and density of nerve fibers immunoreactive to neuropeptide tyrosine, vasoactive intestinal polypeptide and substance P were studied in the reproductive tract of the female rat and compared with acetylcholinesterase-positive ("cholinergic") and noradrenergic nerves. Plexuses of all types of fibers were present in the vagina, uterine cervix, uterine horn and oviduct. In the tubular reproductive organs all of these types of nerve fibers appeared to innervate vascular and non-vascular smooth muscle and nearly all types of fibers formed plexuses subjacent to the epithelium lining the organs. Individual fibers of all classes appeared to innervate fascicles of smooth muscle in the mesometrium of the uterine horn. A few acetylcholinesterase-positive and substance P-immunoreactive fibers were present in the ovary but no vasoactive intestinal polypeptide-immunoreactive nerves were observed. Noradrenergic and neuropeptide tyrosine-immunoreactive nerves were numerous in the ovary where they were seen in the interstitial gland tissue and associated with follicles and blood vessels. It is suggested that these nerves may influence hemodynamic events and non-vascular smooth muscle in such functions as transport of sperm and ova and parturition. Substance P-immunoreactive nerve fibers are likely to be sensory fibers that could have roles in neurohormonal reflexes.

Proliferation of the mammary gland epithelium on days 2, 3, 4, 6, 8, 12, 16, and 19 pregnancy has been studied in mice, by means of radioautography. Each animal received an intraperitoneal injection of 25 pc of tritiated thymidine and was killed one hour later. The inguinal mammary glands were processed for paraffin sectioning and radioautographs prepared using the dipping technique. The rate of mammary epithelial cell proliferation w a s quantitated for each animal by The data showed that the proliferative activity of the mammary epithelium during pregnancy followed a bimodal distribution, The first evidence of a proliferative response to pregnancy was noted on day 3. By day 4, the labeling index reached a maximum of 25.3%. The labeling index declined on days 6 and 8 to 7.5% and 8.0% respectively. On day 12, the labeling index increased to 12.1%, then fell to 7.9% and 1.3% on day 16 and 19, respectively.Separate labeling indexes were determined for the interlobular epithelium (ducts) on day 12, 16, and 19. The data showed that the labeling indexes of the interlobular and intralobular epithelium during these stages of pregnancy were not significantly diffcrcnt. The correlation of the hormones secretcd during pregnancy with the data on mammary epithelial proliferation is discussed.Data on the rate of epithelial cell proliferation in the mammary gland during lactation have been recently reported (Traurig, '67a). It was demonstrated that a wave of proliferative activity occurred in the mammary ducts and alveoli during early lactation. In addition, the advantages of using radioautographic techniques to quantitate mammary epithelial proliferation was discussed. The present investigation extends the use of radioautographic techniques to quantitate the proliferative activity of the mammary gland at close intervals during pregnancy in the mouse. The results are compared to studies in which mammary gland growth was assessed by determinations of whole organ DNA content (Lewin, '57; Brookreson and Turner, '59; Wada and Turner, '59; and Munford, '63 and '64). Also, the correlation of the radioautographic data with available information on the quantity and nature of the hormonal secretions during pregnancy in the mouse is discussed. METIIODSNulliparous CFW mice between three and fis7e months old were mated and, AXAT. Rec., 159: 239-248.

Acetylcholine (ACh) stimulates contraction of the uterus and dilates the uterine arterial supply. Uterine cholinergic nerves arise from the paracervical ganglia and were, in the past, characterized based on acetylcholinesterase (AChE) histochemistry. However, the histochemical reaction for acetylcholinesterase provides only indirect evidence of acetylcholine location and is a nonspecific marker for cholinergic nerves. The present study: (1) reevaluated cholinergic neurons of the paracervical ganglia, (2) examined the cholinergic innervation of the uterus by using retrograde axonal tracing and antibodies against molecules specific to cholinergic neurons, choline acetyltransferase and the vesicular acetylcholine transporter, and (3) examined muscarinic receptors in the paracervical ganglia using autoradiography and a radiolabeled agonist. Most ganglionic neurons were choline acetyltransferase-and vesicular acetylcholine transporter-immunoreactive and were apposed by choline acetyltransferase/vesicular acetylcholine transporter-immunoreactive terminals. Retrograde tracing showed that some cholinergic neurons projected axons to the uterus. These nerves formed moderately dense plexuses in the myometrium, cervical smooth muscle and microarterial system of the uterine horns and cervix. Finally, the paracervical ganglia contain muscarinic receptors. These results clearly reveal the cholinergic innervation of the uterus and cervix, a source of these nerves, and demonstrate the muscarinic receptor content of the paracervical ganglia. Cholinergic nerves could play significant roles in the control of uterine myometrium and vasculature.

The expressions of two closely related synaptic vesicle antigens synaptophysin and synaptoporin were examined in the olfactory system of the adult rat and during pre-and postnatal development. In the adult, immunocytochemistry showed that the continuously regenerating olfactory receptor neurons (primary neurons) produce both synaptophysin and synaptoporin which were localized in the cell bodies of the receptor neurons in the olfactory epithelium, their dendrites, axonal processes in the olfactory nerve and their terminals in the olfactory bulb glomeruli. Furthermore, ultrastructural analysis revealed synaptophysin-and synaptoporin-immunoreactivities associated with synaptic vesicles in most olfactory receptor axonal terminals impinging on dendrites of the mitral and tufted neurons (secondary neurons in the olfactory bulb circuitry) in the olfactory glomeruli. In like manner, tufted neurons, granule and periglomerular neurons (interneurons in the olfactory bulb circuitry) express both synaptophysin and synaptoporin. In contrast, mitral neurons expressed only the synaptophysin antigen which was likewise associated with mitral axonal terminals in their target the olfactory cortex. The patterns of synaptophysin and synaptoporin expressions in mitral neurons (synaptophysin only) and tufted neurons (synaptophysin and synaptoporin) were similar in prenatal, postnatal and adult rats as revealed by immunocytochemistry and in situ hybridization. However, the biosynthesis of synaptophysin and synaptoporin by granule and periglomerular neurons, olfactory bulb interneurons, occurred mainly postnatally.

Nulliparous, CFW mice were injected with 25pc of tritiated thymidine on day 19 of pregnancy, and days 1, 2, 3, 5, 7, 10, 15 and 20 of lactation. The animals were killed one hour after injection. The inguinal manimary glands were removed and processed for paraffin sectioning. Radioautographs were prepared, using the dipping technique.Quantitation of mammary epithelial cell proliferation for the intra-and interlobular (ducts) epithelium was performed by determining the percent of labeled epithelial cells in a large sample of cells (labeling index). It was concluded that epithelial cell sample sizes of 1,000-2,000 cells were adequate to measure mammary epithelial proliferation. A wave of epithelial proliferation was observed during early lactation.hi the intralobular epithelium, a peak labeling index of 11.1% was attained on day two of lactation whereas a peak labeling index of 7.9% was observed on day three of lactation in the interlobular epithelium. Cells of the connective tissue and vascular bed proliferated in response to the growth of the mammary epithelium. Myoepithelial cells were frequently labeled on days two and three of lactation.