The quantity of gastric secretions observed after a brown or white rice meal may be related to the meal buffering capacity, and are accumulated in the distal stomach. The delayed rate of protein emptying in brown rice compared to white rice was most likely due to the accumulation of bran layers in the stomach.

A B S T R A C T We have shown that two unrelated prostaglandin antagonists block both thyrotropin (TSH) and prostaglandins E (PGE1, PGE2) stimulation of thyroidal adenyl cyclase activation and cyclic 3',5'-adenosine monophosphate (cAMP) formation, suggesting that prostaglandins play an important role in regulating thyroid function. To further explore this postulate, we measured prostaglandin content by radioimmunoassay in homogeneous bovine thyroid cell preparations in the presence and absence of TSH. Antibodies to albuminconjugated PGE1 and PGF2. showed specificity for prostaglandins E and F, respectively, but reacted, albeit far less effectively, with heterologous prostaglandins. A double antibody system was used to separate free from antibody-bound PGE1-'H and PGF2.-'H. Thyroid cells were extracted with ethanol/ethyl acetate and the various prostaglandins separated on silicic acid columns. Recoveries of added PGE1-'H and PGF2a-3H through the extraction and separation procedures ranged from 50-80%. The sensitivity of the method was 10-50 pg. Basal thyroid cell content of PGE1 and PGF2a "equivalents" varied between cell preparations (range = 2-6 ng/ 0.2 ml cell suspension) but, in each instance, remained constant during 5-30-min incubations at 370C. TSH, 10-100 mU/ml, increased the levels of cell PGEi and PGF2a "equivalents" 30-80% above basal during 5-15-min incubations. The stimulatory effect was specific for TSH, no increase in PGE, or PGF2a "equivalent" levels being seen with luteinizing hormone (LH), human growth hormone (HGH), adrenocorticotropic hormone (ACTH), or glucagon. These data support the thesis that prostaglandins may mediate TSH effects on thyroid.

Thyrotropin increases prostaglandin levels in isolated thyroid cells. Since comparable results were obtained with butyrated cyclic adenosine monophosphate derivatives as well as with the phosphodiesterase inhibitors quazodine and theophylline, it appears that cyclic adenosine monophosphate mediates this effect of thyrotropin. These observations suggest that intracellular prostaglandins play a role in modulating thyrotropin action on thyroid.

Irradiation of certain meat products produces characteristic objectionable flavors and odors. It has been assumed that the objectionable flavors are due to certain chemical changes, and a number of workers (2,3,6,8,13) have reported values for various chemical components both before and after irradiation. Recently it has been shown that the level of hydrogen sulfide, methyl mercaptan and carbonyls appear to be closely associated with the poor acceptability of irradiated beef, pork and veal (10). However, data are not available in the literature showing the influence of temperature and length of storage upon either the chemical components or panel scores.Consequently, this study was designed to ascertain the effects of length and temperature of storage upon panel scores, carbonyl compounds, hydrogen sulfide, methyl mercaptan, total glutathione, reduced glutathione and the pH of precooked irradiated meats. E X P E R I M E N T A L P R O C E D U R E Preparation and irradiation. The beef, pork and veal were prepared, cooked and irradiated at either 1.86 X 10 6 rads or 2.79 X 10 0 rads as described in a previous publication (10).All samples irradiated at 1.86 X 106 rads were stored at 2" C. in order to prevent the growth of botulinum organisms. The samples irradiated at the higher level (2.79 X 10 6 rads) were stored at 2" C. and 24" C. for the beef and at 2" C., 24" C. and 38" C. for both pork and veal. Storage for both panel and chemical testing was for 0, 1,3 and 6 months. At each of these storage periods, duplicate samples were removed and one was used for taste panel evaluation while the other was used for chemical determinations. Additional samples were available for panel ratings but not for chemical analysis at 12 months for beef and at 9 months for pork.Samples were prepared and presented to a consumer type panel of 18 judges, who rated the samples on the 9-point hedonic scale (12). Although some judges Storage.Panel ratings.

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