Pheochromocytoma cells receptors

Ohta A, Gorelik E, Prasad SJ, Ronchese F, Lukashev D, Wong MK, Huang X, Caldwell S, Liu K, Smith P, Chen JF, Jackson EK, Apasov S, Abrams S, Sitkovsky M (2006) A2A adenosine receptor protects tumors from antitumor T cells. Proc Natl Acad Sci U S A 103(35) 13132-13137 Olah ME, Roudabush FL (2000) Down-regulation of vascular endothelial growth factor expression after A2A adenosine receptor activation in PC 12 pheochromocytoma cells. J Pharmacol Exp Ther 293 779-787... 

The pharmacological activity of decahydroquinoline ci5-195A and analogs in neuromuscular preparations appears to involve noncompetitive blockade both of nicotinic receptor-channels and of voltage-dependent sodium and potassium channels (see reviews in Refs. 3 and 5). Recently, both cis- and rra/i5-decahydroquinolines were shown to block ion flux through nicotinic receptor channels in pheochromocytoma cells and to enhance the rate of desensitization of such nicotinic channels (64,82). 

Disubstituted piperidines (and piperideines) from ants have insecticidal activity and, as venom constituents, serve the ant in a defensive, repellant function (149). 2,6-Disubstituted piperidines are potent noncompetitive blockers of nicotinic receptor-channels in neuromuscular preparations (162) and in electric eel electroplax (163). Synthetic 241D was a potent noncompetitive blocker of nicotinic receptor-channels in both electric eel electroplax and pheochromocytoma cells (64). 

Storch, A. et al., Physostigmine, galanthamine and codeine act as noncompetitive nicotinic receptor agonists on clonal rat pheochromocytoma cells, Eur. J. Pharmacol., 290, 207, 1995. 

Disruption of Ca Homeostasis and Neurological Effects. Neurological and/or neurodevelopmental effects from exposure to PCBs also have been hypothesized to involve interference with calcium homeostatic mechanisms and intracellular second messenger systems by PCB congeners that are not effective Ah receptor agonists (see reviews by Kodavanti and Tilson 1997 Tilson and Kodavanti 1998 Tilson et al. 1998). In agreement with structure-activity relationships observed for PCB effects on dopamine levels in pheochromocytoma cells (Shain et al. 1991), 2,2 -diCB altered intracellular calcium homeostasis in cultured rat cerebellar granule cells (increased free calcium levels and inhibited calcium... 

Isom et al. mentioned endogenous generation of CN and the possibility that CN may function as a neuromodulator in a manner similar to nitric oxide. Brain CN levels are increased by hydromorphone and the effect is blocked by naloxone. Undifferentiated rat pheochromocytoma cells also show increased CN production in response to hydromorphone or morphine. Since PC 12 cells have mainly kappa opiate receptors and no mu receptors, hydromorphone probably acts through kappa receptors to increase CN release. ... 

The pheochromocytoma cell line PC 12 is widely used to study the mechanisms of neuronal cell death following NGF withdrawal. PC 12 cells have the functional receptors for NGF, p75 (p75"8fr)... 

Lukas, R. J. Effects of chronic nicotinic ligand exposure on functional activity of nicotinic acetylcholine receptors expressed by cells of the PC12 rat pheochromocytoma or the TE671/RD human clonal line. J. Neurochem. 56 1134, 1991. 

Answer A. ACEIs slow the progression of diabetic nephropathy and are indicated for management of HTN in such patients. Nitroprusside is used IV in severe HTN or hypertensive crisis, not for management of mild-to-moderate HTN. Losartan, which blocks AT-1 receptors, is associated with teratogenic effects during fetal development, as are the ACEIs. Nonselective beta blockers are not ideal for patients who suffer from peripheral vascular disease, diabetes, or asthma. Reserpine causes the release of amines from tumor cells, exacerbating HTN in pheochromocytoma. 

Viana, G.B., Davis, L.H., and Kauffman, F.C., Effects of organophosphates and nerve growth factor on muscarinic receptor binding number in rat pheochromocytoma PC 12 cells, Toxicol. Appl. Pharmacol, 93, 257, 1988. 

Unfortunately, other biomolecules besides the target a-receptor also are alkylated. Because of its receptor nonselectivity and toxicity, the use of phenoxybenzamine largely is limited to alleviating the sympathetic effects of pheochromocytoma. This tumor of chromaffin cells of the adrenal medulla produces large amounts of epinephrine and norepinephrine, which are released into the bloodstream, producing hypertension and generalized sympathetic stimulation. 

Moughal, NA, Waters, C, Sambi, B, Pyne, S and Pyne, NJ (2004) Nerve growth factor signalling involves interaction between the Trk A receptor and lysophosphatidate receptor 1 systems Nuclear translocation of the lysophosphatidate receptor 1 and Trk A receptors in pheochromocytoma 12 cells. Cellular Signalling, 16, 127-136. 

---