HYPOPHYSEAL MORPHOLOGY 



183 



B. HORMONE CONTENT OF BASOPHIL CELLS 



Evidence of the hormonal content of baso- 

 phil cells can be obtained by the assay of 

 portions of tissue rich in basophil cells and 

 comparison with the results obtained from 

 adjacent portions rich in acidophil cells. In- 

 vestigations of this type have been made 

 by Smith and Smith (1923bj, Voitkevitch 

 (1937a, bj,Herlant ( 1943), Smelser (1944), 

 and Giroud and Martinet (1948). These in- 

 vestigators agree that tissue rich in baso- 

 phil cells has a high content of thyrotrophin 

 and gonadotrophin. It seems that the gon- 

 adotrophic effects include both follicle-stim- 

 ulating and luteinizing actions. Cortico- 

 trophin in both pig and bovine anterior 

 lobes is also somewhat more concentrated 

 in the basophil zone. Because of the preva- 

 lence of chromophobes as well as basophils 

 in the basophil zones, it cannot be inferred 

 that all these hormones are in the basophil 

 cells. Moreover, Smelser has shown that the 

 ratio of the potencies of the two zones is 

 different for thyrotrophin, corticotrophin, 

 and gonadotrophin, so that these hormones 

 seem to be stored in different cells. 



Inasmuch as three distinctive types of 

 basophil cell can be seen in the pars an- 

 terior of some other species, it is likely 

 that a similar diversity occurs in the bovine 

 hypophysis. This species is, however, not 

 favorable for the discernment of specific 

 basophil cell types. 



C. HORMONE CONTENT OF BASOPHIL 

 GRANULES 



The basophil granules are sensitive struc- 

 tures, and lose their glycoprotein content 

 when the cells in which they are contained 

 are damaged, as by freezing or mechanical 

 distortion. It appears that this is the result 

 of the instability of the enclosing membrane 

 to solutions of low osmolar content. 



Thyrotrophin, FSH, and LH are, like the 

 the glycoproteins of basophil granules, solu- 

 ble in water at neutral pH, and are com- 

 pletely extractable from anterior lobes after 

 acetone drying or mechanical disintegra- 

 tion. These hormones seem to be located 

 in membrane-enclosed structures in living 

 cells, because they can be centrifuged down 

 from suspensions of anterior lobe tissue dis- 

 integrated in 0.88 M sucrose. McShan and 



Meyer (1952), and McShan, Rozich and 

 Meyer (1953), using the anterior lobes of 

 castrate rats, were able to recover as much 

 as 75 per cent of the gonadotrophin in a 

 small granule fraction sedimented by cen- 

 trifuging at 20,400 X g for 1 hour. There 

 was evidence that grinding increased the 

 amount of hormone in solution, presumably 

 by disruption of granules. The hormone was 

 extracted from the granules by isotonic sa- 

 line, and from this solution could no longer 

 be sedimented. This behavior is accounted 

 for by the enclosure of the hormone in a 

 membrane with properties similar to that 

 of the mitochondrial membrane and, there- 

 fore, stabilized by high sucrose concentra- 

 tions. 



Herlant (1952a) worked with the anterior 

 lobes of sheep, pig, and beef hypophyses, 

 and obtained a small granule similar to that 

 obtained by McShan and his associates 

 which contained gonadotrophic activity. He 

 found that these small granules gave an 

 intense coloration with the PAS reaction, 

 and thus demonstrated that they were baso- 

 phil granules. It does not seem that the 

 thyrotrophin content of the small granule 

 fraction has been tested except by Brown 

 and Hess (1957) . Their results are not easily 

 interpreted because they sometimes used 

 frozen instead of fresh beef anterior lobes 

 and their fractions are wrongly identified, 

 but it does seem that thyrotrophin can be 

 centrifuged down from material dispersed 

 in sucrose solution (0.25 m in their experi- 

 ments). 



Although these observations are not by 

 themselves conclusive, when considered in 

 conjunction with the cytologic observations 

 presented in the succeeding section, they 

 provide confirmatory evidence for the view 

 that thyrotrophin, FSH, and LH are made 

 by basophil cells and are contained within 

 their characteristic granulation. The behav- 

 ior of corticotrophin in tissue dispersed in 

 solution needs further investigation. 



D. DOES THE PERIODIC ACID-SCHIFF REACTION 



DEMONSTRATE THE HORMONE CONTENT 



OF BASOPHIL CELLS? 



The fact that in the rat pars anterior the 

 amount of PAS reacting material in thyro- 

 trophs, FSH cells, and LH cells, parallels 

 the content of thyrotrophin, FSH, and LH, 



