Acetylcholinesterase containing nerve fibers in guinea pig ovary

Survival role of locally produced acetylcholine in the bovine corpus luteum

The present study was conducted to explore the source of acetylcholine (ACH) in the corpus luteum (CL) and to test our hypothesis of an antiapoptotic role of ACH in the bovine CL and, further, to investigate whether nerve growth factor (NGF), insulin-like growth factor 1 (IGF1), and transforming growth factor beta1 (TGFB1) influence the expression of choline acetyltransferase (CHAT), the biosynthetic enzyme of ACH, in cultured bovine luteal cells. Protein expression and immunolocalization of CHAT were carried out at different stages throughout the luteal phase and in cultured luteal and endothelial cells. ACH was measured in luteal tissue at the different luteal stages and in luteal cells cultured for 8 and 24 h. Cell viability and TUNEL assays were performed on cultured midluteal cells treated with or without tumor necrosis factor alpha (TNF)/interferon gamma (IFNG) in the presence of ACH and its muscarinic (atropine) and nicotinic (mecamylamine) receptor antagonists. The CL was devoid of cholinergic nerve fibers. CHAT immunostaining was evident in luteal, endothelial, and stromal cells in luteal tissue sections and in cultured luteal and endothelial cells. CHAT protein was expressed throughout the cycle without any significant changes. ACH concentration in luteal tissue was not changed during the luteal stages but increased over time and with increased cell numbers in luteal cell cultures. ACH increased cell viability and prevented cell death induced by TNF/IFNG. Atropine significantly attenuated ACH action, whereas mecamylamine had no effect. TNF/IFNG treatment downregulated CHAT expression, whereas NGF, IGF1, and TGFB1 upregulated CHAT expression, in cultured luteal cells. The overall findings strongly suggest a nonneural source and antiapoptotic role of ACH in the bovine CL. Locally produced ACH appears to be regulated by NGF, IGF1, and TGFB1.

The autonomic innervation of the vasa nervorum

Using catecholamine fluorescence and histochemical cholinesterase staining combined with quantitative image analysis a direct autonomic innervation of arteries, arterioles, venules, veins and arterio-venous anastomoses within peripheral nerves was demonstrated in normal as well as in chemically sympathectomized rats. The adrenergic nerves carry varicosities and were more diffused than acetylcholinesterase-containing nerves; the arteries and the arterio -venous anastomoses were more richly innervated. The findings that acetylcholinesterase-positive nerve fibres were unalterated by chemical sympathectomy and were revealed by short incubation times are indicative of a true cholinergic, and probably parasympathetic, innervation of the vasa nervorum. The possible importance of the autonomic innervation of the vasa nervorum in the pathogenesis of some diseases of peripheral nerves is discussed.

Cholinergic nerves in mouse uterus

The topographical distribution of cholinergic nerve fibres in the uterus was studied in normal as well as chemically sympathectomized mice. Our analysis was performed using both transverse sections and whole mounts, in order to analyse the distribution of cholinergic nerves within the various layers of the uterus and to study the morphology of nerve plexuses that supply the organ. Cholinergic nerve fibres were found chiefly around the uterine artery and its primary ramifications. Nerve fibres coming from arterial plexuses are distributed to the myometrium and more infrequently to the endometrium. Groups of acetylcholinesterase positive ganglion cells were located in the cervix. The distribution pattern of the cholinergic innervation of mouse uterus shows important topographical differences. In the tubal end of uterine horn the innervation is poor and cholinergic nerve fibres are organized in a sparse plexus. The number and the density of uterine nerves increase gradually proceeding toward the cervix. The cervix shows the richest innervation. The findings that observed nerve fibres are unaltered by chemical sympathectomy and are revealed using short incubation times suggest their parasympathetic nature.