Abstract
Considerable evidence suggests that both substance P and glutamate play a role in the spinal transmission of the exercise pressor reflex. We tested two hypotheses. First, after a lumbosacral intrathecal injection of a glutamatergic receptor antagonist, the reflex cardiovascular and ventilatory responses to static contraction are attenuated. Second, after a lumbosacral intrathecal injection of a substance P receptor antagonist and a glutamatergic receptor antagonist, the reflex cardiovascular and ventilatory responses to static contraction are abolished. We found that 1) the reflex cardiovascular responses to static contraction were unaffected (P > 0.05) after the intrathecal injection of the N-methyl-D-aspartate (NMDA) receptor antagonists, dl-2-amino-5-phosphonopentanoate (±AP-5) or 3-[(±)-2- carboxypiperazin-4-yl]propyl-1-phosphonic acid (±CPP); 2) the reflex pressor response to static muscular contraction was attenuated by >50% after the intrathecal injection of the non-NMDA receptor antagonist, 6-cyano-7- nitroquinoxaline-2,3-dione (CNQX); and 3) the reflex pressor response to static contraction was almost abolished after the intrathecal injection of the substance P receptor antagonist, CP-96,345, and CNQX. Our results suggest that substance P and glutamate are two neurotransmitters involved in the spinal transmission of the exercise pressor reflex and that substance P and glutamate exert their effects via neurokinin-1 (NK-1) and non-NMDA receptors, respectively.
| Original language | English (US) |
|---|---|
| Journal | American Journal of Physiology - Heart and Circulatory Physiology |
| Volume | 266 |
| Issue number | 5 35-5 |
| State | Published - 1994 |
Fingerprint
Keywords
- autonomic nervous system
- cats
- CP-96,345
- exercise
- groups III and IV muscle afferents
- spinal cord
ASJC Scopus subject areas
- Agricultural and Biological Sciences(all)
- Physiology
Cite this
Blockade of non-NMDA receptors attenuates reflex pressor response to static contraction. / Hill, J. M.; Pickar, J. G.; Kaufman, Marc P.
In: American Journal of Physiology - Heart and Circulatory Physiology, Vol. 266, No. 5 35-5, 1994.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Blockade of non-NMDA receptors attenuates reflex pressor response to static contraction
AU - Hill, J. M.
AU - Pickar, J. G.
AU - Kaufman, Marc P
PY - 1994
Y1 - 1994
N2 - Considerable evidence suggests that both substance P and glutamate play a role in the spinal transmission of the exercise pressor reflex. We tested two hypotheses. First, after a lumbosacral intrathecal injection of a glutamatergic receptor antagonist, the reflex cardiovascular and ventilatory responses to static contraction are attenuated. Second, after a lumbosacral intrathecal injection of a substance P receptor antagonist and a glutamatergic receptor antagonist, the reflex cardiovascular and ventilatory responses to static contraction are abolished. We found that 1) the reflex cardiovascular responses to static contraction were unaffected (P > 0.05) after the intrathecal injection of the N-methyl-D-aspartate (NMDA) receptor antagonists, dl-2-amino-5-phosphonopentanoate (±AP-5) or 3-[(±)-2- carboxypiperazin-4-yl]propyl-1-phosphonic acid (±CPP); 2) the reflex pressor response to static muscular contraction was attenuated by >50% after the intrathecal injection of the non-NMDA receptor antagonist, 6-cyano-7- nitroquinoxaline-2,3-dione (CNQX); and 3) the reflex pressor response to static contraction was almost abolished after the intrathecal injection of the substance P receptor antagonist, CP-96,345, and CNQX. Our results suggest that substance P and glutamate are two neurotransmitters involved in the spinal transmission of the exercise pressor reflex and that substance P and glutamate exert their effects via neurokinin-1 (NK-1) and non-NMDA receptors, respectively.
AB - Considerable evidence suggests that both substance P and glutamate play a role in the spinal transmission of the exercise pressor reflex. We tested two hypotheses. First, after a lumbosacral intrathecal injection of a glutamatergic receptor antagonist, the reflex cardiovascular and ventilatory responses to static contraction are attenuated. Second, after a lumbosacral intrathecal injection of a substance P receptor antagonist and a glutamatergic receptor antagonist, the reflex cardiovascular and ventilatory responses to static contraction are abolished. We found that 1) the reflex cardiovascular responses to static contraction were unaffected (P > 0.05) after the intrathecal injection of the N-methyl-D-aspartate (NMDA) receptor antagonists, dl-2-amino-5-phosphonopentanoate (±AP-5) or 3-[(±)-2- carboxypiperazin-4-yl]propyl-1-phosphonic acid (±CPP); 2) the reflex pressor response to static muscular contraction was attenuated by >50% after the intrathecal injection of the non-NMDA receptor antagonist, 6-cyano-7- nitroquinoxaline-2,3-dione (CNQX); and 3) the reflex pressor response to static contraction was almost abolished after the intrathecal injection of the substance P receptor antagonist, CP-96,345, and CNQX. Our results suggest that substance P and glutamate are two neurotransmitters involved in the spinal transmission of the exercise pressor reflex and that substance P and glutamate exert their effects via neurokinin-1 (NK-1) and non-NMDA receptors, respectively.
KW - autonomic nervous system
KW - cats
KW - CP-96,345
KW - exercise
KW - groups III and IV muscle afferents
KW - spinal cord
UR - http://www.scopus.com/inward/record.url?scp=0028002848&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0028002848&partnerID=8YFLogxK
M3 - Article
C2 - 7911279
AN - SCOPUS:0028002848
VL - 266
JO - American Journal of Physiology
JF - American Journal of Physiology
SN - 0363-6135
IS - 5 35-5
ER -