On the circumstances which modify the action of caffeine and theine upon voluntary muscle / by T. Lauder Brunton and J. Theodore Cash.

  • Brunton, Thomas Lauder, Sir, 1844-1916.
Date:
[1888]
Catalogue details

Licence: Public Domain Mark

Credit: On the circumstances which modify the action of caffeine and theine upon voluntary muscle / by T. Lauder Brunton and J. Theodore Cash. Source: Wellcome Collection.

Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.

    19/30 (page 127)
    Effect of Acids and Alkalies, etc. on Caffeine Rigor. Many important investigations which have been made touching the changes produced in the irritability of striated and unstriated muscular fibre by acids arid alkalis, suggested to us the importance of combining the catfeine solution with these antagonising agencies, in order that any modification of the rigor curve which they might produce could be examined. The results obtained were constant and striking. Lactic acid increases the rapidity of the production of rigor in weak caffeine and theine solutions—not only in contrast with the normal muscle, but also when compared with a corresponding muscle suspended in a solu- tion of caffeine of the same strength but rendered alkaline by KHO. The amount of lactic acid employed was usually 01 (one centigramme) to the 50 c.c. of caffeine mixture admitted to contact with the muscle. We do not lose sight of the fact that not only do these solutions act specifically on the muscle itself, but they may act by combination with the ingredients of the caffeine solution, and also by so altering the fascial covering of the muscle as to render the action of the caffeine weaker or more energetic. The experiments necessary for the elucidation of the questions under this heading may be divided into three series: (1) The action of lactic acid alone. Lactic solution (of the strength usually employed) contrasted with the action of a certain dose of caffeine or theine. (2) The action of lactic acid caffeine solution contrasted with caffeine solution. (3) The action of lactic acid caffeine solution contrasted with potash caffeine solution. Gastrocnemius of a healthy frog of 25 grammes. Companion. M. 01 Lacticacid (Purls.) in 50 c.c. salt solution •7 per cent. Theine -048. Salicylate of soda -015. Salt solution 50 c.c. Lactic acid -OL A faint indication of com- mencing contraction in 8 hrs. 40 mius. Maximum attained in 1 hr. 4 mm. (-r-10). Rigor commenced in 5 hrs. Maximum 73 mm. (-4-10) attained in 10 hi's. and long maintained. It is evident in this case that though lactic acid applied in salt solution may show an increased tendency to cause rigor when compared