GALL BLADDER. 



151 



the left vagus has always given a more marked effect than the right. 

 (Figs. 14, 15, 16.) 



IV. EFFECT OF VARIATION IN THE BLOOD-SUPPLY. 



The stimulant effect on the gall-bladder muscle of hypersemia has 

 already been described in analysing the effects of injecting adrenalin 

 into the circulation. As might be expected, the opposite holds good '> 

 anaemia produced by occlusion of the thoracic aorta causing a very 

 marked inhibition, which affects the tone rather than the rhythmic 

 activity of the muscle. The genuine nature of the effect is proved by 

 obtaining it after separation of the gall-bladder from the liver (Fig. 15). 

 The effect of anaemia corresponds therefore, in this as in other cases, to 



Fig. 17. x ^. Curare. Gall-bladder separated from liver. Chest opened and loop put 

 round thoracic aorta. Blood-pressure from carotid. At P thoracic aorta occluded. 

 At X lever of recorder reached its lower limit. 



that of stimulating the sympathetic nerve-supply 1 . But here, as 

 elsewhere, the inhibitory effect of sympathetic stimulation is shown to 

 be independent of the associated local anaemia by the fact that it is 

 easily obtained when vaso -constriction has been excluded by the action 

 of chrysotoxin. 



1 Cf. Elliott. This Journal, xxxi. p. 164. 1904. 



