Biomaterial Database

Responses of neurons in rostral ventrolateral medulla to activation of cardiac receptors in rats. 2000

D P Li, and H L Pan

Department of Anesthesiology, Wake Forest University School of Medicine, Winston-Salem, North Carolina 27157, USA.

Ischemic stimulation of cardiac receptors reflexly excites the cardiovascular system. However, the supraspinal mechanisms involved in this reflex are not well defined. This study examined the responses of barosensitive neurons in the rostral ventrolateral medulla (RVLM) to stimulation of cardiac receptors and the afferent pathways involved in these responses. Single-unit activity of RVLM neurons was recorded in alpha-chloralose-anesthetized rats. Cardiac receptors were stimulated by epicardial application of 10 microg/ml of bradykinin (BK). Barosensitive neurons were silenced by stimulation of baroreceptors. Application of BK increased the mean arterial pressure from 65.2 +/- 1.9 to 89.3 +/- 2.9 mmHg and excited RVLM barosensitive neurons from 6.2 +/- 0.7 to 10.7 +/- 0.9 impulses/s (P < 0.05, n = 40). BK had no effect on 21 nonbarosensitive neurons. Blockade of stellate ganglia abolished the response of barosensitive neurons to BK. Cervical vagotomy significantly increased the baseline discharges of RVLM barosensitive neurons but had no effect on their responses to BK. Thus this study indicates that stimulation of cardiac receptors selectively activates RVLM barosensitive neurons through sympathetic afferent pathways. This information suggests that the RVLM barosensitive neurons are likely involved in the sympathetic control of circulation during myocardial ischemia.

UI	MeSH Term	Description	Entries
D008012	Lidocaine	A local anesthetic and cardiac depressant used as an antiarrhythmia agent. Its actions are more intense and its effects more prolonged than those of PROCAINE but its duration of action is shorter than that of BUPIVACAINE or PRILOCAINE.	Lignocaine,2-(Diethylamino)-N-(2,6-Dimethylphenyl)Acetamide,2-2EtN-2MePhAcN,Dalcaine,Lidocaine Carbonate,Lidocaine Carbonate (2:1),Lidocaine Hydrocarbonate,Lidocaine Hydrochloride,Lidocaine Monoacetate,Lidocaine Monohydrochloride,Lidocaine Monohydrochloride, Monohydrate,Lidocaine Sulfate (1:1),Octocaine,Xylesthesin,Xylocaine,Xylocitin,Xyloneural
D008297	Male		Males
D008526	Medulla Oblongata	The lower portion of the BRAIN STEM. It is inferior to the PONS and anterior to the CEREBELLUM. Medulla oblongata serves as a relay station between the brain and the spinal cord, and contains centers for regulating respiratory, vasomotor, cardiac, and reflex activities.	Accessory Cuneate Nucleus,Ambiguous Nucleus,Arcuate Nucleus of the Medulla,Arcuate Nucleus-1,External Cuneate Nucleus,Lateral Cuneate Nucleus,Nucleus Ambiguus,Ambiguus, Nucleus,Arcuate Nucleus 1,Arcuate Nucleus-1s,Cuneate Nucleus, Accessory,Cuneate Nucleus, External,Cuneate Nucleus, Lateral,Medulla Oblongatas,Nucleus, Accessory Cuneate,Nucleus, Ambiguous,Nucleus, External Cuneate,Nucleus, Lateral Cuneate
D008839	Microelectrodes	Electrodes with an extremely small tip, used in a voltage clamp or other apparatus to stimulate or record bioelectric potentials of single cells intracellularly or extracellularly. (Dorland, 28th ed)	Electrodes, Miniaturized,Electrode, Miniaturized,Microelectrode,Miniaturized Electrode,Miniaturized Electrodes
D009474	Neurons	The basic cellular units of nervous tissue. Each neuron consists of a body, an axon, and dendrites. Their purpose is to receive, conduct, and transmit impulses in the NERVOUS SYSTEM.	Nerve Cells,Cell, Nerve,Cells, Nerve,Nerve Cell,Neuron
D011311	Pressoreceptors	Receptors in the vascular system, particularly the aorta and carotid sinus, which are sensitive to stretch of the vessel walls.	Baroreceptors,Receptors, Stretch, Arterial,Receptors, Stretch, Vascular,Stretch Receptors, Arterial,Stretch Receptors, Vascular,Arterial Stretch Receptor,Arterial Stretch Receptors,Baroreceptor,Pressoreceptor,Receptor, Arterial Stretch,Receptor, Vascular Stretch,Receptors, Arterial Stretch,Receptors, Vascular Stretch,Stretch Receptor, Arterial,Stretch Receptor, Vascular,Vascular Stretch Receptor,Vascular Stretch Receptors
D001920	Bradykinin	A nonapeptide messenger that is enzymatically produced from KALLIDIN in the blood where it is a potent but short-lived agent of arteriolar dilation and increased capillary permeability. Bradykinin is also released from MAST CELLS during asthma attacks, from gut walls as a gastrointestinal vasodilator, from damaged tissues as a pain signal, and may be a neurotransmitter.	Arg-Pro-Pro-Gly-Phe-Ser-Pro-Phe-Arg,Bradykinin Acetate, (9-D-Arg)-Isomer,Bradykinin Diacetate,Bradykinin Hydrochloride,Bradykinin Triacetate,Bradykinin, (1-D-Arg)-Isomer,Bradykinin, (2-D-Pro)-Isomer,Bradykinin, (2-D-Pro-3-D-Pro-7-D-Pro)-Isomer,Bradykinin, (2-D-Pro-7-D-Pro)-Isomer,Bradykinin, (3-D-Pro)-Isomer,Bradykinin, (3-D-Pro-7-D-Pro)-Isomer,Bradykinin, (5-D-Phe)-Isomer,Bradykinin, (5-D-Phe-8-D-Phe)-Isomer,Bradykinin, (6-D-Ser)-Isomer,Bradykinin, (7-D-Pro)-Isomer,Bradykinin, (8-D-Phe)-Isomer,Bradykinin, (9-D-Arg)-Isomer,Arg Pro Pro Gly Phe Ser Pro Phe Arg
D004333	Drug Administration Routes	The various ways of administering a drug or other chemical to a site in a patient or animal from where the chemical is absorbed into the blood and delivered to the target tissue.	Administration Routes, Drug,Administration Route, Drug,Drug Administration Route,Route, Drug Administration,Routes, Drug Administration
D006321	Heart	The hollow, muscular organ that maintains the circulation of the blood.	Hearts
D000344	Afferent Pathways	Nerve structures through which impulses are conducted from a peripheral part toward a nerve center.	Afferent Pathway,Pathway, Afferent,Pathways, Afferent