230 



Metabolism 



occurs when the chorda is stimulated, but the blood flow through 

 the gland increases to about the same degree as in the absence 

 of atropine and the oxygen consumption increases 10-100 per cent 

 (compared with 200-400 per cent in the absence of atropine). It 

 appears that the secretory response is the most sensitive and the 

 vascular response the least sensitive to the effects of atropine 

 (Barcroft, 1914; Terroux, Sekelj and Burgen, 1959; Stromblad, 

 1959)- 



I" 5 



I os 



-3=y 



o 2 



90 

 10 



50Y 

 30 



\h- 



\ 



*-*■» 



2 4 6 



Min 



2 4 



Fig. 



1 I.i. Arterial blood flow (ABF ml./g/min) and oxygen consumption 

 (0 2 /u.l./g/min) of dog submaxillary gland. 



During the period marked by the bar the chorda tympani was stimulated at 5 c.p.s. • — • 

 before administration of atropine X — X 15 minutes after 1 mg/kg. of atropine. No secretion 

 occurred. O — O 35 minutes after the atropine (Terroux, Sekelj and Burgen, 1950). 



In vitro techniques have shown a complete block by atropine 

 of the metabolic effects of acetylcholine (Deutsch and Raper, 1936; 

 Brock, Druckrey and Herken, 1938). This is presumably due to 

 the larger doses of atropine used in these experiments although it 

 is well known that atropine antagonizes the effects of injected 

 acetylcholine more readily than the effects of parasympathetic 

 stimulation (see Hilton and Lewis, 1957). Similar increases of 

 oxygen consumption have been obtained in the cat submaxillary 

 gland stimulated by adrenaline or the sympathetic (Barcroft and 

 Piper, 1912; Barcroft, 1914; Deutsch and Raper, 1936; Stromblad, 

 1957 and 1959). The amount of oxygen required in the secretion 

 of sympathetic saliva is less than that for chorda saliva (Stromblad, 



