These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.
Pubmed for Handhelds
PUBMED FOR HANDHELDS
Search MEDLINE/PubMed
Title: Comparison between the effect of static contraction and tendon stretch on the discharge of group III and IV muscle afferents. Author: Hayes SG, Kindig AE, Kaufman MP. Journal: J Appl Physiol (1985); 2005 Nov; 99(5):1891-6. PubMed ID: 15994238. Abstract: The exercise pressor reflex is evoked by both mechanical and metabolic stimuli. Tendon stretch does not increase muscle metabolism and therefore is used to investigate the mechanical component of the exercise pressor reflex. An important assumption underlying the use of tendon stretch to study the mechanical component of the exercise pressor reflex is that stretch stimulates the same group III mechanosensitive muscle afferents as does static contraction. We have tested the veracity of this assumption in decerebrated cats by comparing the responses of group III and IV muscle afferents to tendon stretch with those to static contraction. The tension-time indexes as well as the peak tension development for both maneuvers did not significantly differ. We found that static contraction of the triceps surae muscles stimulated 18 of 30 group III afferents and 8 of 11 group IV afferents. Similarly, tendon stretch stimulated 14 of 30 group III afferents and 3 of 11 group IV afferents. However, of the 18 group III afferents that responded to static contraction and the 14 group III afferents that responded to tendon stretch, only 7 responded to both stimuli. On average, the conduction velocities of the 18 group III afferents that responded to static contraction (11.6 +/- 1.6 m/s) were significantly slower (P = 0.03) than those of the 14 group III afferents that responded to tendon stretch (16.7 +/- 1.5 m/s). We have concluded that tendon stretch stimulated a different population of group III mechanosensitive muscle afferents than did static contraction. Although there is some overlap between the two populations of group III mechanosensitive afferents, it is not large, comprising less than half of the group III afferents responding to static contraction.[Abstract] [Full Text] [Related] [New Search]