Central nervous system control of gastrointestinal function
Research in my laboratory focuses on central nervous system control of gastrointestinal function. Our goals are to determine the roles of GABA and nicotinic acetylcholine receptors in clinically relevant problems such as diabetes mellitus and gastroesophageal reflux disease. The methods used in this research include patch clamp electrophysiology in slices of the brain stem, in vivo recordings of end organ function using pharmacological stimuli such as microinjection of drug into the brain and intravenous drug infusion, and electron microscopy coupled with immunohistochemistry. These techniques are used to map the pathways in the brain that affect end organs; namely, the stomach, lower esophageal sphincter and cecum. We are also investigating the roles of glucose and insulin in diabetes mellitus, locating glucose-sensing areas in the brain and finding out how these areas can be used to treat problems associated with the disease.
In regards to sex differences, we are currently doing research in the field of drugs affecting respiratory activity. Specifically, we have found that drugs that block the N-methyl aspartyl glutamate (ie, NMDA) receptor produce a respiratory disturbance called apneustic breathing. Most important, there is a sex difference among rats in terms of susceptibility of this event occurring.
- Sahibzada N, Ferreira M Jr, Williams B, Wasserman A, Vicini S, Gillis RA. Nicotinic ACh receptor subtypes on gastrointestinally projecting neurones in the dorsal motor vagal nucleus of the rat. J Physiol. 545:1007-16, 2002.
- Wasserman AM, Ferreira M Jr, Sahibzada N, Hernandez YM, Gillis RA. GABA-mediated neurotransmission in the ventrolateral NTS plays a role in respiratory regulation in the rat. Am J Physiol Regul Integr Comp Physiol. 283:R1423-41, 2002
- Ferreira M Jr, Sahibzada N, Shi M, Panico W, Niedringhaus M, Wasserman A, Kellar KJ, Verbalis J, Gillis RA. CNS site of action and brainstem circuitry responsible for the intravenous effects of nicotine on gastric tone. J Neurosci. 22:2764-2779, 2002
- Ferreira M Jr, Browning KN, Sahibzada N, Verbalis JG, Gillis RA, Travagli RA. Glucose effects on gastric motility and tone evoked from the rat dorsal vagal complex. J Physiol. 536:141-152, 2001
- Ferreira M, Ebert SN, Perry DC, Yasuda RP, Baker CM, Davila-Garcia MI, Kellar KJ, Gillis RA. Evidence of a Functional alpha7-Neuronal Nicotinic Receptor Subtype Located on Motoneurons of the Dorsal Motor Nucleus of the Vagus. J Pharmacol Exp Ther. 296:260-269, 2001