Secretory Physiology Section
Building 10 Room 1N113
10 Center Dr MSC 1190
Bethesda, MD 20892-1190
Our studies utilize a variety of approaches, including electrophysiology, cellular imaging, molecular biology, as well as biochemistry to determine the molecular basis of Ca2+ entry in salivary gland acini and the role of Ca2+ entry in fluid secretion. Our recent and ongoing studies are directed towards identifying the function, regulation, trafficking and assembly of the transient receptor potential channel, TRPC1. We have provided evidence that TRPC1 is an essential component of the agonist-stimulated Ca2+ influx mechanism that is required for sustained saliva secretion. We have identified two other important components of this mechanism, the calcium channel, Orai1, and the ER regulator of calcium channels, STIM1. Current studies are directed to understand and define the individual contributions of TRPC1 and Orai1 to salivary fluid secretion. We are also interested in identifying the regulation of the water channel, AQP5, during stimulation of the gland and secretion. Our work has led to the identification of TRPV4 as an essential TRP channel that is involved in cellular volume regulation. In addition, other TRPC channels, TRPC3 and TRPC6, could also have important role in regulating other aspects of salivary gland function. These studies are ongoing.
EDUCATION: 1973, B.Sc. (Biology), Isabella Thoburn College, Lucknow, India; 1975 M.Sc. (Biochemistry), Lucknow University, Lucknow, India. 1980 Ph.D. (Biochemistry), Madurai Kamaraj University Madurai, India.
- Heteromeric TRPV4-C1 channels contribute to store-operated Ca(2+) entry in vascular endothelial cells. Cell Calcium. 2011 Dec; 50 (6)Ma X, Cheng KT, Wong CO, O'Neil RG, Birnbaumer L, Ambudkar IS, Yao X.
- VASCULARIZING THE TUMOR: TRP CHANNELS AS MOLECULAR TARGETS. Pla AF, Avanzato D, Munaron L, Ambudkar IS.Am J Physiol Cell Physiol. 2011 Aug 10. [Epub ahead of print]
- The dynamic complexity of the TRPC1 channelosomeOng HL, Ambudkar IS. . Channels (Austin). 2011 Sep 1;5(5):424-31. Epub 2011 Sep 1.
- TRPV4 mediates tumor-derived endothelial cell migration via arachidonic acid-activated actin remodeling. Fiorio Pla A, Ong HL, Cheng KT, Brossa A, Bussolati B, Lockwich T, Paria B, Munaron L, Ambudkar IS. Oncogene. 2011 Jun 20. doi: 10.1038/onc.2011.231. [Epub ahead of print]
- Dissection of calcium signaling events in exocrine secretion. Ambudkar IS. Neurochem Res. 2011 Jul;36(7):1212-21. Epub 2011 May 2. Review.