Requirement of guinea pigs

Cortisone or ACTH administration did not alter the ascorbic acid requirements of guinea pigs for prevention of scurvy (P8, H7). As would be expected, ACTH or cortisone did not diminish the antiscorbutic effectiveness of dehydroascorbic acid in guinea pigs (C13), nor did they affect the plasma levels in patients with rheumatoid arthritis (Ml). Both ACTH and cortisone do, however, increase the excretion of ascorbic acid in the urine on large intakes (Kl). 

Blevins, B. G. (1983). Amino add requirements of guinea pigs. XIII. The indispensable amino add component at levels of total nitrogen near or above the requirement. M.S. Thesis, University of Missouri, Columbia. 

Both the enzymes were prepared by a special technique from the insoluble portion of guinea pig liver mitochondria, and they are quite specific with respect to the requirement of pyridine nucleotide (H9, Hll). However, dehydrogenases catalyzing reaction (25) with NAD as coenzyme have been reported (Mil, S13, T3), thus confirming the importance of the source of the enzyme and the purification procedure employed. 

Freund and Stone have found that the minimum amount of tubercle bacilli for sensitization of guinea-pigs was 0.0004 mg., whereas 0.2 mg. of wax D in a water-oil emulsion was required the greater activity of the whole cells might be due, in part, to their greater surface, whereas it cannot be excluded that the activity of the wax D preparations might be due to an impurity. 

Single-channel records of guinea pig cardiomyocytes in the presence of 50 iiM veratridine (internally applied) show short events of normal conductance. As noted above, these records also demonstrate two types of events after modification that would require another bound state, O , of intermediate conductance with a mean open time of 19 ms (E=-120 mV), rising to 86 ms at E=-10 mV. The analogous values for state O were 4.5 and 16 ms, respectively (22°-25°C Sunami et al. 1993). From the sequence of events the authors conclude that 0 should connect with 0 but also with two more states, and R>. Interestingly, state 0 proves to be more resistant to tetrodotoxin than O, in contrast to observations in other preparations (see Sect. 5.5). 

The search for new and effective treatment modalities requires the availability of adequate screening tests. Although no model adequately reflects the events that occur in human arthritic conditions, several in vivo and in vitro assays are used. The most common in vivo animal assays measure the ability of anti-inflammatory drugs to inhibit edema induced in the rat paw by carrageenan (a mucopolysaccharide derived from a sea moss of the Chondrus species), to inhibit adjuvant arthritis in rats induced by Mycobacterium butyricum or M. tuberculosis, to inhibit granuloma formation usually induced by the implantation of a cotton pellet beneath the abdominal skin of rats, or to inhibit erythema of guinea pig skin as a result of exposure to ultraviolet radiation. In vitro techniques include the ability of NSAIDs to stabilize erythrocyte membranes or, more commonly, to inhibit the biosynthesis of prostaglandins, particularly in cultured human synoviocytes and chondrocytes, and monocyte culture fluid stimulated bovine synoviocytes and chondrocytes. 

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