Physiology

BRIAN A. JACKSON, Ph.D. Professor Ph.D. University of Sheffield, 1977 Office: MS-501 Medical Center 0298 Tel: (859) 323-8503 Lab: MS-570, Tel: 323-8035 E-mail: brian.jackson@uky.edu Curriculum Vita (pdf)

We are currently conducting studies in two distinct organ systems, the kidney and the adrenal medulla. Our renal study is testing the hypothesis that NaCl homeostasis is maintained at least in part, by an entero-renal endocrine axis in which urinary NaCl excretion is rapidly regulated by two recently identified peptides, uroguanylin (UGN) and guanylin (GN), which are released from the gastrointestinal tract in response to altered NaCl intake. This work utilizes classical renal physiological techniques such as in vitro microperfusion and in vivo micropuncture, in combination with cellular and molecular biological analysis of microdissected renal tubular segments and renal epithelial cells in culture.

The long-term goal of our adrenal project is to identify factors that modulate catecholamine synthesis and secretion in adrenal medullary chromaffin cells. Currently, we are testing the hypothesis that both intrinsic and extrinsic factors can affect both processes by modulating the activity of critical signal transduction pathways including nicotinic receptor-dependent increases in intracellular calcium via voltage-gated calcium channels, and peptidergic receptor-dependent increases in intracellular cAMP. These experiments utilize diverse techniques including patch-clamp analysis of ion channels, fluorescence imaging of intracellular calcium, carbon-fiber amperometric analysis of single-cell c atecholamine secretion, RT-PCR and northern blotting.

Recent publications:

Adams JM, Legan SJ, Ott CE, Jackson BA, Modulation of stress-induced increases in plasma epinephrine by estrogen in the female rat. J. Neurosci Res. 79: 360-367.

Carrithers SL, Hill MJ, Johnson BR, Chang JJ, Shah RG, Trumbore JN, Sun C, Mann EA, Forte LR, Jackson BA, Ott CE, Giannella RA, Greenberg RN. Guanylin and uroguanlyn induce natriuresis in mice lacking guanylyl cyclase-C receptor. Kidney Int. 65:4053, 2004.

Grider J, Ott E, Jackson B. Fendoldopam-dependent inhibition of NaCl transport in the medullary thick ascending limb of the rat; mechanism of action. Europ. J. Pharmacol. 473:185-190, 2003.

Carrithers SL, Jackson BA, Greenberg RN, Ott Ce. Regulation of intestinal guanylin and uroguanylin expression by dietary salt intake. Regulatory Peptides 107:87-95, 2002.

Li X, Titlow WB, Jackson BA, Giltiay N, Nikolova Karakashian M, Uittenbogaard A, Smart EJ. High-density lipoprotein binding to scavenger receptor class B, type-1 activates endothelial nitric oxide synthesis in a ceramide-dependent manner(pdf). J. Biol. Chem. 277:11058-11063, 2002.

Other Publications