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Biotech / Medical : Vivus: into single digits -- Ignore unavailable to you. Want to Upgrade?

To: BigKNY3 who wrote (64)	2/9/1998 10:38:00 PM
From: MIKE DUBIS	Read Replies (1) \| Respond to of 1016

Who could this person be???

To: BigKNY3 who wrote (64)	2/10/1998 11:55:00 PM
From: Tunica Albuginea	Read Replies (1) \| Respond to of 1016

BigKNY3, here is the reference you requested. It is more authoritative than your source.The reason why doctors have a hard time evaluating the true efficacy of drugs is because of the blue smoke and mirrors emanating from the PR Depts of most Drug Cos and the uninformed support they get from lay people, including those with MBAs or PhDs but not MD degrees.This is why also we have the other big scam: the health food industry, but that is another issue.This data was previously posted by me and this posting would not have been necessary if you had taken the time to read them ( or at least the original textbook ).Somewhere along the line you need to explain the " blue halo " effect of Viagra on patients ( you haven't so far ). PS Don't spend too much time trying to convince DrDale Russell in your lonesome corner of all this mumbojumbo on PDE selectivity. DrRussell knows better than that. Maybe you should read his preface to this thread. TA ============================================================= From GOODMAN & GILLMAN'S THE PHARMACOLOGICAL BASIS OF THERAPEUTICS NINTH EDITION, 1997 ( The no 1 , US Medical School, Textbook of Pharmacology ) I abstracted in quotation, verbatim, the specific answer to your questions; I capitalized important points. *********************** Chapter 34 Page 833 . " MANY organs, including cardiac muscle, contain members OF ALL KNOWN PDE isoenzyme families (Bode et al., 1991: Nicholson et al., 1991)." "The SPECIFICITY of the "selective" inhibitors noted in Table 34-8 is RESTRICTED for most PDE isoenzymes to a RELATIVELY NARROW concentration range, with NON-SPECIFIC INHIBITION evident at HIGHER concentrations. " (tab;e 34-8 is from Nickolson 1991, summarized as follows: PDE-I: CNS modulation PDE-III: Positive inotropism PDE- IV: Airway smooth muscle relaxation PDE- V: Penile erection PDE-VI: Photoreceptor PDE-VII: Skeletal muscle "In addition, MOST of these inhibitors have OTHER known pharmacoloaical activities ' ****************** The original posts for the above:: - phosphodiesterase ( PDE ) sideffects - PDE ):Taken from Goodman & Gillman 1996 ED.Textbook of pharmacology. www3.techstocks.com - www3.techstocks.com

To: BigKNY3 who wrote (64)	2/17/1998 3:05:00 PM
From: Tunica Albuginea	Respond to of 1016

Big K, concerning " blue halos " side effect of Viagra and possible retinal degeneration/ blindness. I have made several calls and found out several items. I will post some of the preliminary findings and replies to your points. First however let me point out you still have not told us why patients get blue halos. This can be an early sign of toxicity. For example "color vision " seen when a patient is on digitalis, means that it is at toxic levels with risk of sudden cardiac death due to an arrhythmia. The points: 1)"In the definitive research book on PDEs "Phosphodiesterase Inhibitors" by Christian Schudt et al, Academic Press." Answer: -Book was published in 1996. Their data thus only goes to ~ 1993 ( there is usually a 2-3 year lag on references ). -from reading your post one could get the opinion that the word "definitive" means that that's it. All work is done, and this is all there is to know and this is not so in fact as I will point out. 2)"-"The type VI PDEs are found in the photoreceptors and are involved in visual signaling pathways". Answer: - the reason PDE VI have been primarily described in the retina is because =it is the most abundant =it is the most easily reached in the surface aerea, in the rods. -fact is that PDE VI was initially part of PDE V !!;( PDEV is the one in the penis, the one that Viagra inhibits ). -PDE V was later separated into PDE V and VI; BUT, 75% OF penile PDE V has the SAME STRUCTURE as retinal PDE VI and share the same characteristics and possibly react the same to Viagra. - The PDE content of retinal cones is not known and can very well contain PDE V. I can't comment on the textbook you have quoted because it is a subreference book. I am in the process of getting it through interlibrary loan and I will comment when I see it. It is very easy to quote something out of context. Again, so far what we know for sure is that: -Patients on Viagra get "blue halos", [ and "other visual disturbances" per DrBennett's article in Feb (* Geriatrics, that I posted earlier ).] -Color disturbances can be a sign of some form of tissue injury. -No Retinal Electrograms were done that we know off on patients receiving Viagra, which is the only sure way to detect early retinal damage. -PDEs as a group are a very toxic group of drugs; thus it would be unusual for one of them (n Viagra) to be different. however am still in process of gathering more data. I will post as they come in. TA