Vasoactive intestinal polypeptide in cholinergic neurons of exocrine glands: Functional significance of coexisting transmitters for vasodilation and secretion

Abstract

The vasodilation induced by nerve stimulation in exocrine glands-e.g., submandibular salivary gland (1), tongue (2), sweat glands (3), and nasal mucosa (4)-is largely atropine resistant, whereas secretion easily can be blocked by muscarinic antagonists. The occurrence of a subpopulation of vasodilatory nerves was first suggested, but later a kinin mechanism was suggested to be responsible for this vasodilation (5-9). MATERIALS AND METHODSTen cats (body weight 2-4 kg) of both sexes were used for immunohistochemical studies. In two of these cats the superior cervical ganglion was excised unilaterally 14 days before they were killed. In four other cats vinblastine sulfate (Sigma) (1% in 0.9% NaCl) was locally applied to the submandibular and sphenopalatine ganglia and to pancreas 24 hr before perfusion with ice-cold 10% (vol/vol) formalin (21). These ganglia and parts of the submandibular gland, the nasal mucosa, tongue, lung, and pancreas were then processed for indirect immunohistochemical studies according to Coons (22) as described (see ref. 18) by use of a VIP antibody (5603-5; for detail about this antiserum, see refs. 23 and 24) and AcChoE staining (18,25,26). In some cases, immunohistochemical analysis for VIP and AcChoE staining were performed on the same section. Alternatively, adjacent sections were processed for the respective procedure. The latter approach was used because Triton X-100 (added to VIP antiserum to enhance penetration of antibodies) inactivated AcChoE (18,27). For details and validity of procedures and for controls, see ref. 18. Physiological experiments were done in 15 cats anesthetized with chloralose (50 mg/kg) plus urethane (100 mg/kg) intravenously. The trachea was cannulated. The blood pressure was recorded via a femoral artery. Rectal temperature was kept constant at 38°C. The submandibular gland, its duct, and nerve supply were exposed. The duct was cannulated with a polyethylene tube (PE 50) and salivation was measured with a drop recorder. The chorda-lingual nerve was cut, and the peripheral cut end was mounted to a bipolar platinum electrode. Preganglionic stimulation was performed with square wave pulses of either 2 or 15 Hz, 8 V, and a duration of 1 msec. To measure the venous outflow from the gland, we introduced a polyethylene catheter (PE 160) into the external jugular vein after all branches, except the one draining the submandibular gland, had been tied. Blood flow was measured by a drop recorder and blood was reinfused into the cephalic vein with a peristaltic pump. Heparin (1000 IU/kg) was given intravenously. The Abbreviations: VIP, vasoactive intestinal polypeptide; AcCho, acetylcholine; AcChoE, acetylcholinesterase. 1651The publication costs of this article were defrayed in part by page charge payment. This article must therefore be hereby marked "advertisement" in accordance with 18 U. S. C. §1734 solely to indicate this fact.

Vitamin D and parotid gland function in the rat.

“…Vasoactive intestinal polypeptide (VIP) is released from intraglandular cholinergic nerve endings during parasympathetic stimulation, and has been shown to evoke atropine-resistant vasodilatation in salivary glands (Lundberg, Anggard, Fahrenkrug, H6kfelt & Mutt, 1980;Ekstrom, Brodin, Ekman, Hakanson, Mansson & Tobin, 1985). Lundberg et al (1980) further demonstrated that close arterial infusion of anti-VIP antibodies blocked this vasodilatation along with salivation by cat submandibular gland. An alternate proposal is that the local hyperaemia of salivation is mediated by kallikreins released directly from secreting salivary glands; the physiological importance of this mechanism, however, has been questioned (Schachter, 1969;Regoli & Barabe, 1980).…”

Cholinergic and VIPergic vasodilator actions of parasympathetic nerves on the thyroid blood flow in rats.

“…Vasoactive intestinal peptide (VIP), a polypeptide containing 28 amino acid residues, was first isolated from hog upper intestinal tissue by SAID and MUTT (1970). Parasympathetic vasodilatory actions have been intensively studied in the salivary gland of the cat by LUNDBERG et al (1980), EDWARDS (1980), andANDERSSON et al (1982). They reported that salivary blood vessels received both parasympathetic cholinergic and VIPergic vasodilatory fibers.…”

Salivary VIP concentrations are elevated in humans after acute stress

“…VIP/Ach containing nerves are found at high concentrations in the adrenal glands, salivary glands and pancreas (Igarashi et al, 2011). VIP is involved in vasodilation and, therefore, it has a function in counteracting the vasoconstrictive effects of the sympathetic response (Igarashi et al, 2011;Lundberg et al, 1980). There is also evidence which suggests that VIP may play a role in the regulation of the HPA-axis (Nussdorfer et al, 1998).…”