AJP - Heart Fuel your research with LabChart
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

Am J Physiol Heart Circ Physiol 278: H871-H877, 2000;
0363-6135/00 $5.00
This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Right arrow Citation Map
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in ISI Web of Science
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via ISI Web of Science (7)
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Legramante, J. M.
Right arrow Articles by Kaufman, M. P.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Legramante, J. M.
Right arrow Articles by Kaufman, M. P.
Vol. 278, Issue 3, H871-H877, March 2000

Group III muscle afferents evoke reflex depressor responses to repetitive muscle contractions in rabbits

J. M. Legramante1, G. Raimondi1, C. M. Adreani2, S. Sacco1, F. Iellamo1, G. Peruzzi1, and M. P. Kaufman2

1 Dipartimento di Medicina Interna, Cattedra di Fisiopatologia Medica, Universita' di Roma "Tor Vergata," 00173 Rome, Italy; and 2 Division of Cardiovascular Medicine, Departments of Internal Medicine and Human Physiology, University of California, Davis, California 95616

Repetitive-twitch contraction of the hindlimb muscles in anesthetized rabbits consistently evokes a reflex depressor response, whereas this type of contraction in anesthetized cats evokes a reflex pressor response in about one-half of the preparations tested. Rapidly conducting group III fibers appear to comprise the afferent arm of the reflex arc, evoking the depressor response to twitch contraction in rabbits because electrical stimulation of their axons reflexly decreases arterial pressure. In contrast, electrical stimulation of the axons of slowly conducting group III and group IV afferents reflexly increases arterial pressure in rabbits. In the present study, we examined the discharge properties of group III and IV muscle afferents and found that the former (i.e., 13 of 20), but not the latter (i.e., 0 of 10), were stimulated by 5 min of repetitive-twitch contraction (1 Hz) of the rabbit triceps surae muscles. Moreover, most of the group III afferents responding to contraction appeared to be mechanically sensitive, discharging in synchrony with the muscle twitch. On average, rapidly conducting group III afferents responded for the 5-min duration of 1-Hz repetitive-twitch contraction, whereas slowly conducting group III afferents responded only for the first 2 min of contraction. We conclude that rapidly conducting group III afferents, which are mechanically sensitive, are primarily responsible for evoking the reflex depressor response to repetitive-twitch contractions in anesthetized rabbits.

dynamic exercise; autonomic nervous system; arterial blood pressure; sensory nerves; somatic afferents; breathing


This article has been cited by other articles:


Home page
 Am. J. Physiol. Heart Circ. Physiol.Home page
D. Michikami, A. Kamiya, T. Kawada, M. Inagaki, T. Shishido, K. Yamamoto, H. Ariumi, S. Iwase, J. Sugenoya, K. Sunagawa, et al.
Short-term electroacupuncture at Zusanli resets the arterial baroreflex neural arc toward lower sympathetic nerve activity
Am J Physiol Heart Circ Physiol, July 1, 2006; 291(1): H318 - H326.
[Abstract] [Full Text] [PDF]

Home page
 J. Appl. Physiol.Home page
K. Tokizawa, M. Mizuno, Y. Nakamura, and I. Muraoka
Venous occlusion to the lower limb attenuates vasoconstriction in the nonexercised limb during posthandgrip muscle ischemia
J Appl Physiol, March 1, 2004; 96(3): 981 - 984.
[Abstract] [Full Text] [PDF]

Home page
 Am. J. Physiol. Heart Circ. Physiol.Home page
N. Hayashi
Exercise pressor reflex in decerebrate and anesthetized rats
Am J Physiol Heart Circ Physiol, June 1, 2003; 284(6): H2026 - H2033.
[Abstract] [Full Text] [PDF]

Home page
 Physiol. Rev.Home page
S. C. Gandevia
Spinal and Supraspinal Factors in Human Muscle Fatigue
Physiol Rev, October 1, 2001; 81(4): 1725 - 1789.
[Abstract] [Full Text] [PDF]


HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Visit Other APS Journals Online