Pituitary Adenylate Cyclase-Activating Peptide in the Adrenal Gland of Mammals: Distribution, Characterization and Responses to Drugs

Abstract

The occurrence, cellular distribution and nature of the 27-amino acid form of pituitary adenylate cyclase-activating peptide (PACAP-27) in the adrenal glands of mammals was investigated by means of immunohistochemistry, radioimmunoassay and chromatography. The concentrations (pmol/g wet weight) of PACAP-27-like immunoreactivity (LI) varied considerably between the species examined: mouse (n = 8), 12.1 ± 2.0; hamster (n = 4), 9.1 ± 1.5; rat (n = 13), 2.0 ± 0.3; cow (n = 3), 0.8 ± 0.1, and pig (n = 5), 0.7 ± 0.1. Upon HPLC, the immunoreactivity in extracts of rat, mouse and hamster adrenals coeluted with synthetic PACAP-27 while the immunoreactivity in extracts of cow and pig adrenals eluted as less hydrophobic material. Immunohistochemistry revealed the presence of PACAP-27-LI in the noradrenaline-storing chromaffin cells of the adrenal medulla. No nerve fibers exhibiting PACAP-27-LI could be detected. The effects of drug administration in vivo on the stores of PACAP-27-LI in the rat adrenal were studied and compared with the effects on the adrenal stores of neuropeptide Y (NPY)-LI. Splanchnic activation following insulin-induced hypoglycemia elicited a 41% depletion of NPY-LI 2 h after insulin injection, while the concentrations of PACAP-27-LI remained unchanged. Two days after reserpine administration the stores of PACAP-27-LI and NPY-LI were depleted by 62 and 41%, respectively. Two days later, the concentrations of NPY-LI were increased to 216% of controls, while the concentrations of PACAP-27-LI were similar to that of controls. Taken together with data from the literature, our findings suggest that PACAP may be involved in the regulation of adrenomedullary activity in more than one mammalian species. The stimuli that regulate the synthesis and release of PACAP-27 in the adrenal gland remains to be identified but seems to differ from those involved in the regulation of NPY.

Pituitary Adenylate Cyclase-Activating Polypeptide and Its Receptors: 20 Years after the Discovery

“…In the airways, PACAPcontaining fibers innervate smooth muscle bundles and blood vessels in the trachea as well as small bronchioles 292 VAUDRY ET AL. Brandenburg et al, 1997;Moller et al, 1997a,b;Nogi et al, 1997a;Nielsen et al, 1998a Trigeminal ganglia ϩ ϩ ϩ ϩ Moller et al, 1993;Mulder et al, 1994;Dun et al, 1996a Vigh et al, 1993;Kimura et al, 1994;Mikkelsen et al, 1995;Köves et al, 1998;Heinzlmann et al, 2008 FS, GH, PRL, and Frödin et al, 1995;Shiotani et al, 1995;Dun et al, 1996b;Moller and Sundler, 1996;Nielsen et al, 1998a Chromaffin cells ϩ -/ϩ -/ϩ Tabarin et al, 1994;Dun et al, 1996a;Holgert et al, 1996;Moller and Sundler, 1996 Shioda et al, 1994;Hannibal and Fahrenkrug, 1995;Yanaihara et al, 1998 Mature spermatids -/ϩ Hannibal andYanaihara et al, 1998;Li et al, 2004Epididymal spermatozoa -Leung et al, 1998Sertoli cells --Kononen et al, 1994Shioda et al, 1994;Hannibal and Fahrenkrug, 1995 Gräs et al, 1996;Scaldaferri et al, 1996;Lee et al, 1999a PITUITARY ADENYLATE CYCLASE-ACTIVATING POLYPEPTIDE 293 in the lung (Cardell et al, 1991;…”

PAC1 Receptor Activation by PACAP-38 Mediates Ca2+ Release from a cAMP-dependent Pool in Human Fetal Adrenal Gland Chromaffin Cells

“…The chemicals used in the present study were obtained from the following sources: RNAqueous TM -4PCR purchased from Ambion (Austin, TX); dithiothreitol, p(dT) [12][13][14][15][16][17][18] , rRNasin Ribonuclease Inhibitor, Moloney murine leukemia virus reverse transcriptase (RT) and DNA ladder from Promega (Madison, WI); deoxy-NTPs and Taq DNA polymerase from Amersham Pharmacia Biotech (Piscataway, NJ); Xestospongin C, U73122, forskolin, thapsigargin, and H-89 from Calbiochem-Novabiochem Corp. (San Diego, CA); methacholine, sodium orthovanadate, nicotine, and DNase from Sigma-Aldrich Canada Ltd (Oakville, Ontario, Canada); collagenase, MEM Eagle's medium and OPTI-MEM from Invitrogen (Burlington, Ontario, Canada); (R p )-cAMPS from Biomol (Plymouth Meeting, PA); Fluo-4 from Molecular Probes (Eugene, OR); PACAP-38 was synthesized by the solid phase methodology as previously described (22); and PACAP (6 -38) was from American Peptide Co. (Sunnyvale, CA). All other chemicals were of A grade purity.…”

“…RNA content and quality were determined photometrically. 5 g of total RNA was denatured (70°C, 10 min) and reverse-transcribed in the presence of 200 M p(dT) [12][13][14][15][16][17][18] at 42°C for 50 min in 20 l of 1ϫ RT buffer (25 mM Tris-HCl, pH 8.3, 37.5 mM KCl, 1.5 mM MgCl 2 ) containing: 15 mM dithiothreitol, 200 M deoxy-NTPs, 25 units of rRNasin ribonuclease inhibitor, and 200 units of Moloney murine leukemia virus RT. Inactivation of the enzyme (70°C, 10 min) was followed by glyceraldehyde-3-phosphate dehydrogenase PCR to assess the quality of the cDNA template (24).…”

“…PACAP and its receptors are actively expressed in the adrenal medulla (12)(13)(14). In particular, we have previously demonstrated the occurrence of PACAP-38 (15) and PACAP binding sites (16) in chromaffin cells from 16-to 20-week-old fetal human adrenal glands.…”

Time-Dependent Effects of the Neuropeptide PACAP on Catecholamine Secretion

“…3,4 The adrenal gland is innervated by a dense network of PACAP-immunoreactive fibers, and abundant PACAP binding sites occur on the surface of chromaffin cells. 5,6 In addition to the classic preganglionic neurotransmitter acetylcholine, the noncholinergic transmitter PACAP is likely to play an important role in governing both secretion and synthesis of catecholamines in chromaffin cells. [7][8][9][10] We recently reported that PACAP triggers both catecholamine secretion and transcriptional activation of the regulated secretory protein chromogranin A in PC12 pheochromocytoma cells.…”