176 



HYPOPHYSIS AND GONADOTROPHIC HORMONES 



ify the lipid content of the adjacent adrenal 

 cortex, whereas similar implants from the 

 acidophilic zone produced a discharge of 

 lipid followed by a re-accumulation. The 

 response, therefore, to the local presence of 

 tissue from the acidophilic zone was simi- 

 lar to that produced by injections of cortico- 

 trophin. Inasmuch as Halmi and Bogdanove 

 (1951) have shown that rat pituitaries 

 which have lost their acidophil granules 

 after total thyroidectomy still contain nor- 

 mal amounts of corticotrophin, it would 

 seem that corticotrophin is not a constituent 

 of the acidophil granules in the rat. 



My own assays of the basophil and acido- 

 phil zones of the pig pars anterior, using the 

 ascorbic acid depletion assay, showed that 

 both zones contained high concentrations of 

 corticotrophin, but that there was a higher 

 concentration in the basophil zone than in 

 the acidophil zone. In this species, as in the 

 rat and bovine, corticotrophin is not asso- 

 ciated with acidophil granules, and although 

 a different situation may be found in other 

 species, I would ascribe Herlant's (1952b, 

 1953a ) results to the absorption of the hor- 

 mone by the granules or other particles sed- 

 imenting with them. The results of implan- 

 tation experiments are explicable by the fact 

 that corticotrophin is present in acidophil 

 and basophil zones in about the same 

 amount; apparently the histologic response 

 is modified by the presence of other mate- 

 rials, different for each zone. 



Inasmuch as somatotrophin and prolactin 

 are the two hormones which are in higher 

 concentration in the acidophil zones of pig 

 and beef anterior lobes, it is concluded that 

 these hormones are in the acidophil cells. 

 The two hormones are not necessarily pro- 

 duced in the same cell, because in many 

 mammals two types of acidophil cells can be 

 seen. Purves and Sirett (1959) have shown 

 that prolactin and somatotrophin have dif- 

 ferent disti'ilnitions in the anterior lobe of 

 the wallaby hyjiophysis, indicating a sepa- 

 rate origin for each hormone. 



!■:. HORMONE CONTENT OF ACIDOPHIL 

 GRANULES 



Acidophil granules prepared by the differ- 

 ential centrifugation of the susi)ension pre- 

 pared by disintegrating the anterior lobes of 

 sheep, pig, and ])ovin(> hypophyses in hyjicr- 



tonic sucrose solution, were examined for 

 their hormone content by Herlant (1952a, 

 b; 1955). The easily sedimented granules 

 contain prolactin and somatotrophin, 

 whereas thyrotrophin and gonadotrophins 

 remain in the supernatant, from which they 

 can be thrown down only by centrifuging at 

 much higher speeds. The granules also con- 

 tain corticotrophin, but in view of the well 

 known tendency of this hormone to become 

 firmly bound to proteins, this finding is of 

 doubtful significance. Only if it were shown 

 that corticotrophin added to a suspension 

 of granules did not become bound to them 

 could the association of this hormone with 

 the granules be regarded as indicative of its 

 in vivo location. 



The results of Brown and Hess (1957) 

 are not in conflict with Herlant's findings, 

 although they interpreted them as showing 

 somatotrophin in the mitochondrial frac- 

 tion. Having experimented with both sheep 

 and beef pituitaries, I am of the opinion 

 that Brown and Hess underestimated the 

 rate of sedimentation of acidophil granules, 

 and that there is no likelihood of sediment- 

 ing the mitochondria in this material and 

 leaving the acidophil granules in the super- 

 natant. 



Combining the evidence obtained from 

 assays of tissue and of separated granules, 

 it can be concluded that cells of the acido- 

 phil cell class produce somatotrophin and 

 prolactin, and that these hormones are 

 stored in their granules. 



F. ACIDOPHIL CELL TYPES 



In some species an easy differentiation of 

 the acidophil cells of the pars anterior into 

 two si)ecific types is obtained by staining 

 methods. The differentiation depends on the 

 tendency of the granules in one cell type to 

 be stained orange with Orange G, whereas 

 the other type is stained a red color with 

 azocarmine in the azan method, or with 

 acid fuchsin in Crossmon's (1937) method, 

 or with erythrosin in the Cleveland-Wolfe 

 method used by Wolfe, Cleveland and 

 Campbell (1933)^. 



It will be convenient for the purposes of 

 discussion to adopt the term ''carminophil" 

 used by Friedgood and Dawson (1940) for 

 red-stained cells, and the term ''orange- 

 ophil" used by Lacour (1950) for orange- 



