In addition to performing its prime function as a vehicle for scientific communications of varied colora- tions, Molecular and Cellular Biochemistry is again focusing on two subjects which it treats in depth. One of these is a book issue dealing with the transglutaminase reaction. The other is this issue that deals with induction and modulation of enzymes. This is a very broad subject that calls for broader coverage than could be included in one book issue. However, I have elected to include only certain contributions that serve as general examples of the principles involved. There are six articles on enzyme regulation in hepatocyte culture. These include arginase and argino-succi- nate synthetase, y-glutamyl transferase and plasminogen activitor. Other regulatory enzymes that are discussed are protein kinases, 2,3-bisphosphoglycerate synthetases, carbamoyl phosphate synthetase, heme oxygenase, cytochrome P-450, tyrosine hydroxylase, fatty acid synthetase, acetyl eoA carboxylase, among others. Also included is the regulation of several enzyme messengers RNAs. As in the past, subscribers to the journal will receive this double volume as a continuation of regular issues of the journal Molecular and Cellular Biochemistry. This double volume will also be available separately in the form of a book issue to interested readers through Martinus Nijhoff Publishers. v.A. Najjar Part I Molecular and Cellular Biochemistry 53;54,11-21 (1983). (c) 1983, Martinus 1\ ij hoff Publishers. Boston. Printed in The Netherlands.

In addition to performing its prime function as a vehicle for scientific communications of varied colora- tions, Molecular and Cellular Biochemistry is again focusing on two subjects which it treats in depth. One of these is a book issue dealing with the transglutaminase reaction. The other is this issue that deals with induction and modulation of enzymes. This is a very broad subject that calls for broader coverage than could be included in one book issue. However, I have elected to include only certain contributions that serve as general examples of the principles involved. There are six articles on enzyme regulation in hepatocyte culture. These include arginase and argino-succi- nate synthetase, y-glutamyl transferase and plasminogen activitor. Other regulatory enzymes that are discussed are protein kinases, 2,3-bisphosphoglycerate synthetases, carbamoyl phosphate synthetase, heme oxygenase, cytochrome P-450, tyrosine hydroxylase, fatty acid synthetase, acetyl eoA carboxylase, among others. Also included is the regulation of several enzyme messengers RNAs. As in the past, subscribers to the journal will receive this double volume as a continuation of regular issues of the journal Molecular and Cellular Biochemistry. This double volume will also be available separately in the form of a book issue to interested readers through Martinus Nijhoff Publishers. v.A. Najjar Part I Molecular and Cellular Biochemistry 53;54,11-21 (1983). (c) 1983, Martinus 1\ ij hoff Publishers. Boston. Printed in The Netherlands.

the GABA increase takes place and (2) the area of the brain that may mediate the anticonvulsant Investigation of the physiology, biochemistry, activity. Three compounds that increase brain pharmacology and anatomy of GAB A and GABA GABA by distinct mechanisms were used in these containing neural systems, continues to reveal the studies: di-n-propylacetate (DPA, sodium val rich complexities associated with this neuroactive proate, Depakene(R)), amino-oxyacetic acid amino acid (see recent symposia 1,2,3). Advances (AOAA) and y-vinyl GABA (GVG). in the pharmacology of GABA-mimetic agents In the next sections, the metabolism of GABA have resulted in the development of compounds and a brief historical account of the relationship that can selectively activate GABA receptors (4,5, between GABA and anticonvulsant activity are 6, 7), inhibit the synthetic and degradative enzymes outlined followed by a discussion ofthe biochemical for GABA (8, 9) or affect the neuronal and glial and pharmacological effects of the three drugs. In uptake processes for GABA (10, 11). This has particular, the literature pertaining to the suppres already had a significant impact on our under sion of seizures and the correlation between anti standing of the role of GABA in convulsions and a convulsant action and increases in brain G ABA will range of other CNS functions including feeding be examined. (12), cardiovascular control (13), motor activity (14) and release of pituitary hormones (15). Before 1."