Abstract
Although group III and IV fibers are known to compose the afferent pathway of the reflex arc causing the pressor response to static muscular contraction, little is known about the neurotransmitters released by these muscle afferents. Somatostatin might be one of these neurotransmitters because this peptide is found in the terminals of fine afferent fibers ending in the dorsal horn of the lumbar spinal cord. Therefore, in chloralose-anesthetized cats, the reflex pressor response to static contraction was examined before and after subarachnoid injections onto the lumbosacral cord of a peptide antagonist to somatostatin. We found that before giving the antagonist, the pressor response to contraction of the triceps surae muscles in 12 cats averaged 33 ± 4 mm Hg, while 37 ± 7 minutes after giving the antagonist, the pressor response averaged only 18 ± 3 mm Hg (p < 0.001). In contrast, the antagonist to somatostatin had no effect on either the pressor response to electrical stimulation of the cut central end of the sciatic nerve or the pressor response to stimulation of the posterior diencephalon. Furthermore, subarachnoid injection of a peptide antagonist to luteinizing hormone-releasing hormone had no effect on the reflex pressor response to static contraction. Our findings are consistent with the hypothesis that somatostatin plays a role in the spinal transmission of the contraction-induced pressor reflex arising from hind limb skeletal muscle.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 18-24 |
| Number of pages | 7 |
| Journal | Circulation Research |
| Volume | 62 |
| Issue number | 1 |
| State | Published - 1988 |
| Externally published | Yes |
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ASJC Scopus subject areas
- Physiology
- Cardiology and Cardiovascular Medicine
Cite this
Attenuation of the reflex pressor response to muscular contraction by an antagonist to somatostatin. / McCoy, K. W.; Rotto, D. M.; Rybicki, K. J.; Kaufman, Marc P.
In: Circulation Research, Vol. 62, No. 1, 1988, p. 18-24.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Attenuation of the reflex pressor response to muscular contraction by an antagonist to somatostatin
AU - McCoy, K. W.
AU - Rotto, D. M.
AU - Rybicki, K. J.
AU - Kaufman, Marc P
PY - 1988
Y1 - 1988
N2 - Although group III and IV fibers are known to compose the afferent pathway of the reflex arc causing the pressor response to static muscular contraction, little is known about the neurotransmitters released by these muscle afferents. Somatostatin might be one of these neurotransmitters because this peptide is found in the terminals of fine afferent fibers ending in the dorsal horn of the lumbar spinal cord. Therefore, in chloralose-anesthetized cats, the reflex pressor response to static contraction was examined before and after subarachnoid injections onto the lumbosacral cord of a peptide antagonist to somatostatin. We found that before giving the antagonist, the pressor response to contraction of the triceps surae muscles in 12 cats averaged 33 ± 4 mm Hg, while 37 ± 7 minutes after giving the antagonist, the pressor response averaged only 18 ± 3 mm Hg (p < 0.001). In contrast, the antagonist to somatostatin had no effect on either the pressor response to electrical stimulation of the cut central end of the sciatic nerve or the pressor response to stimulation of the posterior diencephalon. Furthermore, subarachnoid injection of a peptide antagonist to luteinizing hormone-releasing hormone had no effect on the reflex pressor response to static contraction. Our findings are consistent with the hypothesis that somatostatin plays a role in the spinal transmission of the contraction-induced pressor reflex arising from hind limb skeletal muscle.
AB - Although group III and IV fibers are known to compose the afferent pathway of the reflex arc causing the pressor response to static muscular contraction, little is known about the neurotransmitters released by these muscle afferents. Somatostatin might be one of these neurotransmitters because this peptide is found in the terminals of fine afferent fibers ending in the dorsal horn of the lumbar spinal cord. Therefore, in chloralose-anesthetized cats, the reflex pressor response to static contraction was examined before and after subarachnoid injections onto the lumbosacral cord of a peptide antagonist to somatostatin. We found that before giving the antagonist, the pressor response to contraction of the triceps surae muscles in 12 cats averaged 33 ± 4 mm Hg, while 37 ± 7 minutes after giving the antagonist, the pressor response averaged only 18 ± 3 mm Hg (p < 0.001). In contrast, the antagonist to somatostatin had no effect on either the pressor response to electrical stimulation of the cut central end of the sciatic nerve or the pressor response to stimulation of the posterior diencephalon. Furthermore, subarachnoid injection of a peptide antagonist to luteinizing hormone-releasing hormone had no effect on the reflex pressor response to static contraction. Our findings are consistent with the hypothesis that somatostatin plays a role in the spinal transmission of the contraction-induced pressor reflex arising from hind limb skeletal muscle.
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UR - http://www.scopus.com/inward/citedby.url?scp=0023928824&partnerID=8YFLogxK
M3 - Article
VL - 62
SP - 18
EP - 24
JO - Circulation Research
JF - Circulation Research
SN - 0009-7330
IS - 1
ER -