Vasopressin calcium

These include nicotinic acetylcholine receptors, neuronal calcium channels, muscle sodium channels, vasopressin receptors, and iV-methyl-D-aspartate (NMDA) receptors. Some general features of the structure, function, and evolution of biologically active peptides isolated from Conus venom are presented. 

Figure 4 Schematic representation of the Ca2+-transporting systems affecting cellular calcium homeostasis during hormonal stimulation, oq = oq-adrenergic receptor VP = vasopressin receptor PLC = phospholipase C PI = phosphatidylinositol PIP = phospha-tidylinositol-4-phosphate PIP2 = phosphatidylinositol-4,5-biphosphate IP3 = inositol-1,4,5-triphosphate DG = diacylglycerol PKC = protein kinase C. (Modified from Refs. 125 and 285.)...

SK Joseph, JR Williamson. (1983). The origin, quantitation, and kinetics of intracellular calcium mobilization by vasopressin and phenylephrine in hepatocytes. J Biol Chem 258 10425-10432. 

Berridge MJ 1997 Elementary and global aspects of calcium signalling. J Physiol 499 291—306 Broad LM, Cannon TR, Taylor CW 1999 A non-capacitative pathway activated by arachidonic acid is the major Ca2+ entry mechanism in rat A7r5 smooth muscle cells stimulated with low concentrations of vasopressin. J Physiol 517 121-134 Byron KL, Taylor CW 1995 Vasopressin stimulation of Ca2+ mobilization, two bivalent cation entry pathways and Ca2+ efflux in A7r5 rat smooth muscle cells. J Physiol 485 455—468... 

On the other hand, mercuric chloride decreased both spontaneous and evoked transmitter liberation at the frog neuromuscular junction [98] as well as the release of vasopressin from the pituitary gland [99] it was suggested that these effects are mediated via changes in the intracellular calcium ion concentration. 

Because adrenergic agents such as P-blockers find such extensive use as hypotensive drugs, the etiology and drug combination treatment of hypertension are of considerable interest. A discussion in any detail of this complex and confusing field goes beyond the scope of this book, however. Other aspects of hypertension will be discussed in connection with the renin and vasopressin systems and calcium channel blockers. 

Three subtypes of vasopressin G protein-coupled receptors have been identified. Via receptors mediate the vasoconstrictor action of vasopressin V , receptors potentiate the release of ACTH by pituitary corticotropes and V 2 receptors mediate the antidiuretic action. Via effects are mediated by activation of phospholipase C, formation of inositol trisphosphate, and increased intracellular calcium concentration. V2 effects are mediated by activation of adenylyl cyclase. 

Sands, JM, Naruse, M, Baum, M, Jo, I, Hebert, SC, Brown, EM and Harris, HW, 1997, Apical extracellular calcium/polyvalent cation-sensing receptor regulates vasopressin-elicited water permeability in rat kidney irmer medullary collecting duct, J Clin Invest 99 1399—1405... 

Endocrine and metabolic Blood tests Serum concentrations of pituitary horrmones (TSH, LH, FSH, ACTH, growth hormone, prolactin, vasopressin) serum concentrations of other hormones (insulin parathyroid hormone, glucagon, calcitonin, vitamin D) and serum electrolyte concentrations (sodium, potassium, calcium, magnesium)... 

Fig. 11. Potentiation by glucagon of the actions of vasopressin on the calcium and [3H]IP, content of isolated rat hepatocytes previously labeled with [3H]myo-inositol. Hepatocytes were incubated with [ H]myo-inositol to label the inositol phospholipids and then for S min with the concentrations of vasopressin shown in the presence or absence of 1 nM glucagon. Total cell calcium and [3H]IP, were measured as described in Refs. 139 and 140. Reproduced from Ref. 5 by permission of the authors and publisher.

Lightman SL, Iversen LL, Forsling ML (1982) Dopamine and [D-ALA2, D-LEU5]enkephalin inhibit the electrically stimulated neurohypophyseal release of vasopressin in vitro evidence for calcium-dependent opiate action. J Neurosci 2 78-81. 

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