Upregulation, receptor

The dramatic heightening of aggressive behavior in morphine-withdrawn animals may be due to dopamine receptor upregulation (Gianutsos et al. 1975 Lai et al. 1975). Morphine and methadone inhibit dopamine receptors in the central nervous system (CNS) suggesting possible disuse... 

Teal, J.J., and Holtzman, S.G. Discriminative stimulus effects of cyclazocine in the rat. J. Pharmacol Fxp Ther 212 368-376, 1980. Tempel, A. Gardner, E-L. and Zukin, R.S. Visualization of opiate receptor upregulation by light microscopy autoradiography. Proc Natl Acad Sci USA 81 3893-3897, 1984. 

Wonnacott, S. The paradox of nicotinic acetylcholine receptor upregulation by nicotine. Trends Pharmacol. Sci. 11 216, 1990. 

Stefanski, R., Justinova, Z., Hayashi, T. et al. Sigmal receptor upregulation after chronic methamphetamine self-administration in rats a study with yoked controls. Psychopharmacology. 175 68, 2004. 

The answer is a. (Katzung, p 590.) Bile acids are absorbed primarily in the ileum of the small intestine. Cholestyramine binds bile acids, preventing their reabsorption in the jejunum and ileum. Up to 10-fold greater excretion of bile acids occurs with the use of resins. The increased clearance leads to increased cholesterol turnover of bile acids. Low-density lipoprotein receptor upregulation results in increased uptake of LDL. This does not occur in homozygous familial hypercholesterolemia because of lack of functioning receptors. 

Adolescent nicotine exposure results in pronounced and persistent nicotinic cholinergic receptor upregulation in male rats and hippocampal cell damage in females (Trauth et al. 1999). During and following nicotine treatment as adolescents, female rats show impaired rearing and locomotor activity, whereas males are unaffected. On the other hand, improved performance was observed in passive avoidance (Trauth et al. 2000). 

Follesa P, Ticku MK (1996) NMDA receptor upregulation molecular studies in cultured mouse cortical nem-ons after chronic antagonist exposure. J Neimosci 16 2172-2178 Fourgeaud L, Mato S, Bouchet D, et al (2004) A single in vivo exposure to cocaine abolishes endocannabinoid-mediated long-term depression in the nucleus accimibens. J Neimosci 24 6939-6945... 

Smit MJ, Timmerman H, Alewijnse AE, Leurs R. From histamine H2 receptor regulation to reclassification of H2 antagonists inverse agonism as the basis for H2 receptor upregulation. Receptors Channels 1998 5 99-102. 

Tsuda, M., Toyomitsu, E., Komatsu, T., Masuda, T., Kunifusa, E., Nasu-Tada, K., Koizumi, S., Yamamoto, K., Ando, J., and Inoue, K. (2008). Fibronectin/integrin system is involved in P2X(4) receptor upregulation in the spinal cord and neuropathic pain after nerve injury. Glia 56, 579-585. 

Follesa P, Ticku MK. 1996. NMDA receptor upregulation molecular studies in cultured mouse cortical neurons after chronic antagonist exposure. J. Neurosci. 16(7) 2172-78... 

Yobum, B.C., Duttaroy, A., Shah, S., Davis, T., 1994. Opioid antagonist-induced receptor upregulation effects of concurrent agonist administration. Brain Res. 33, 237-240. 

Chronic use of beta blockers (e.g., in angina, HTN) leads to receptor upregulation. 

Hoffman, J.F., Linderman, J.J., Omann, G.M. (1996). Receptor upregulation, internalization, and interconverting receptor states critical components of a quantitative description of N-formyl peptide-receptor dynamics in the neutrophil. /. Biol. Chem. 271, 18394-18404. 

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