Tags

Type your tag names separated by a space and hit enter

A fall in arterial blood pressure produced by inhibition of the caudalmost ventrolateral medulla: the caudal pressor area.
J Auton Nerv Syst. 1994 Nov; 49(3):235-45.JA

Abstract

The caudal edge of the ventrolateral medulla was mapped to localize sites where microinjections of L-glutamate (L-glu) produce pressor responses in paralyzed and artificially ventilated urethane-anesthetized rats. Pressor responses ranging from 15 to 65 mmHg were obtained when L-Glu (0.25 M, 200 nl) was microinjected in the ventral medullary surface within an area localized between the rootlets of the XII and first cervical nerves, lateral to the pyramids and just medial to the spinal roots of the XI cranial nerve. This area has been called the caudal pressor area (CPA). Inhibition of the CPA by microinjection of GABA or glycine resulted in marked falls (15-45 mmHg) of arterial blood pressure (AP). Hypotension in response to CPA inhibition was also obtained in unanesthetized decerebrate animals. Cardiovascular responses to CPA stimulation or inhibition depend on the activity of neurons in the rostral ventrolateral medulla (RVLM). During hypotension provoked by RVLM inhibition, pressor responses to CPA stimulation were abolished. Conversely, pressor responses to RVLM stimulation were maintained during hypotension produced by inhibition of CPA. Pressor response to bilateral carotid occlusion were not reduced by CPA inhibition. We conclude that cells in the caudal most ventrolateral medulla exert a tonic pressor activity that contributes to maintenance of basal levels of the vasomotor tone and arterial blood pressure, its inhibition, however, does not prevent the pressor response to carotid occlusion.

Authors+Show Affiliations

Department of Physiology, Escola Paulista de Medicina, São Paulo, Brazil.No affiliation info availableNo affiliation info availableNo affiliation info availableNo affiliation info available

Pub Type(s)

Journal Article
Research Support, Non-U.S. Gov't

Language

eng

PubMed ID

7806775

Citation

Possas, O S., et al. "A Fall in Arterial Blood Pressure Produced By Inhibition of the Caudalmost Ventrolateral Medulla: the Caudal Pressor Area." Journal of the Autonomic Nervous System, vol. 49, no. 3, 1994, pp. 235-45.
Possas OS, Campos RR, Cravo SL, et al. A fall in arterial blood pressure produced by inhibition of the caudalmost ventrolateral medulla: the caudal pressor area. J Auton Nerv Syst. 1994;49(3):235-45.
Possas, O. S., Campos, R. R., Cravo, S. L., Lopes, O. U., & Guertzenstein, P. G. (1994). A fall in arterial blood pressure produced by inhibition of the caudalmost ventrolateral medulla: the caudal pressor area. Journal of the Autonomic Nervous System, 49(3), 235-45.
Possas OS, et al. A Fall in Arterial Blood Pressure Produced By Inhibition of the Caudalmost Ventrolateral Medulla: the Caudal Pressor Area. J Auton Nerv Syst. 1994;49(3):235-45. PubMed PMID: 7806775.
* Article titles in AMA citation format should be in sentence-case
TY - JOUR T1 - A fall in arterial blood pressure produced by inhibition of the caudalmost ventrolateral medulla: the caudal pressor area. AU - Possas,O S, AU - Campos,R R,Jr AU - Cravo,S L, AU - Lopes,O U, AU - Guertzenstein,P G, PY - 1994/11/1/pubmed PY - 2001/3/28/medline PY - 1994/11/1/entrez SP - 235 EP - 45 JF - Journal of the autonomic nervous system JO - J. Auton. Nerv. Syst. VL - 49 IS - 3 N2 - The caudal edge of the ventrolateral medulla was mapped to localize sites where microinjections of L-glutamate (L-glu) produce pressor responses in paralyzed and artificially ventilated urethane-anesthetized rats. Pressor responses ranging from 15 to 65 mmHg were obtained when L-Glu (0.25 M, 200 nl) was microinjected in the ventral medullary surface within an area localized between the rootlets of the XII and first cervical nerves, lateral to the pyramids and just medial to the spinal roots of the XI cranial nerve. This area has been called the caudal pressor area (CPA). Inhibition of the CPA by microinjection of GABA or glycine resulted in marked falls (15-45 mmHg) of arterial blood pressure (AP). Hypotension in response to CPA inhibition was also obtained in unanesthetized decerebrate animals. Cardiovascular responses to CPA stimulation or inhibition depend on the activity of neurons in the rostral ventrolateral medulla (RVLM). During hypotension provoked by RVLM inhibition, pressor responses to CPA stimulation were abolished. Conversely, pressor responses to RVLM stimulation were maintained during hypotension produced by inhibition of CPA. Pressor response to bilateral carotid occlusion were not reduced by CPA inhibition. We conclude that cells in the caudal most ventrolateral medulla exert a tonic pressor activity that contributes to maintenance of basal levels of the vasomotor tone and arterial blood pressure, its inhibition, however, does not prevent the pressor response to carotid occlusion. SN - 0165-1838 UR - https://www.unboundmedicine.com/medline/citation/7806775/A_fall_in_arterial_blood_pressure_produced_by_inhibition_of_the_caudalmost_ventrolateral_medulla:_the_caudal_pressor_area_ L2 - https://linkinghub.elsevier.com/retrieve/pii/0165-1838(94)90170-8 DB - PRIME DP - Unbound Medicine ER -