PubMed Health⌕ Search

Biomedical subjects

V Manne

Publications and source records attributed to V Manne.

At least 19 recordsLinked to original sources
PubMed2001

Preclinical antitumor activity of BMS-214662, a highly apoptotic and novel farnesyltransferase inhibitor.

BMS-214662 is a potent and selective inhibitor of farnesyltransferase (FTI). In rodent fibroblasts transformed by oncogenes, BMS-214662 reversed the H-Ras-transformed phenotype but not that of K-Ras or other oncogenes. In soft agar growth assays, BMS-214662 showed good potency in inhibiting H-ras-transformed rodent cells, A2780 human ovarian carcinoma tumor cells, and HCT-116 human colon carcinoma tumor cells. Inhibition of H-Ras processing in HCT-116 human colon tumor cells was more rapid than in H-Ras-transformed rodent fibroblast tumors. BMS-214662 is the most potent apoptotic FTI known and demonstrated broad spectrum yet robust cell-selective cytotoxic activity against a panel of cell lines with diverse histology. The presence of a mutant ras oncogene was not a prerequisite for sensitivity. Athymic and conventional mice were implanted s.c. with different histological types of human and murine tumors, respectively. BMS-214662 was administered both parenterally and p.o. and was active by all these routes. Curative responses were observed in mice bearing staged human tumor xenografts including HCT-116 and HT-29 colon, MiaPaCa pancreatic, Calu-1 lung, and EJ-1 bladder carcinomas. A subline of HCT-116, HCT-116/VM46, resistant to many standard cytotoxic agents by means of a multiple drug resistance mechanism, remained quite susceptible to BMS-214662, and borderline activity was achieved against N-87 human gastric carcinoma. Two murine tumors, Lewis lung carcinoma and M5076 sarcoma, were insensitive to the FTI. In a study performed using Calu-1 tumor-bearing mice, no obvious schedule dependency of BMS-214662 was observed. The FTI, BMS-214662, demonstrated broad spectrum activity against human tumors, but murine tumors were not as sensitive.

Alkyl and Aryl Transferases↗
PubMed2000

Discovery of (R)-7-cyano-2,3,4, 5-tetrahydro-1-(1H-imidazol-4-ylmethyl)-3- (phenylmethyl)-4-(2-thienylsulfonyl)-1H-1,4-benzodiazepine (BMS-214662), a farnesyltransferase inhibitor with potent preclinical antitumor activity.

Continuing structure-activity studies were performed on the 2,3,4, 5-tetrahydro-1-(imidazol-4-ylalkyl)-1,4-benzodiazepine farnesyltransferase (FT) inhibitors. These studies demonstrated that a 3(R)-phenylmethyl group, a hydrophilic 7-cyano group, and a 4-sulfonyl group bearing a variety of substituents provide low-nanomolar FT inhibitors with cellular activity at concentrations below 100 nM. Maximal in vivo activity in the mutated K-Ras bearing HCT-116 human colon tumor model was achieved with analogues carrying hydrophobic side chains such as propyl, phenyl, or thienyl attached to the N-4 sulfonyl group. Several such compounds achieved curative efficacy when given orally in this model. On the basis of its excellent preclinical antitumor activity and promising pharmacokinetics, compound 20 (BMS-214662, (R)-7-cyano-2,3,4, 5-tetrahydro-1-(1H-imidazol-4-ylmethyl)-3-(phenylmethyl)-4-(2-thie nyl sulfonyl)-1H-1,4-benzodiazepine) has been advanced into human clinical trials.

3T3 Cells↗
PubMed2000

Contribution of Ras GTPase/MAP kinase and cytochrome P450 metabolites to deoxycorticosterone-salt-induced hypertension.

We recently reported that norepinephrine and angiotensin II activate the Ras/mitogen-activated protein (MAP) kinase pathway through generation of a cytochrome P450 (CYP450) and lipoxygenase metabolites. The purpose of this study was to determine the contribution of Ras/MAP kinase to deoxycorticosterone acetate (DOCA)-salt-induced hypertension in rats. Administration of DOCA and 1% saline drinking water to uninephrectomized rats for 6 weeks significantly elevated mean arterial blood pressure (MABP) (166+/-5 mm Hg, n=19) compared with that of normotensive controls (95+/-5 mm Hg, n=7) (P<0.05). The activity of Ras and MAP kinase measured in the heart was increased in DOCA-salt hypertensive rats. Infusion of the Ras farnesyl transferase inhibitors FPT III (138 ng/min) and BMS-191563 (694 ng/min) significantly (P<0.05) attenuated MABP to 139+/-4 mm Hg (n=14) and 126+/-1 mm Hg (n=4), respectively. Moreover, infusion of MAP kinase kinase inhibitor PD-98059 (694 ng/min) also reduced MABP in hypertensive rats. Morphological studies of the kidney showed that treatment of rats with FPT III, which reduced Ras activity, minimized the hyperplastic occlusive arteriosclerosis and fibrinoid vasculitis observed in untreated hypertensive rats. In addition, the rise in CYP450 activity and MABP in hypertensive rats was prevented by the CYP450 inhibitor aminobenzotriazole (50 mg/kg) and was associated with a decrease in Ras and MAP kinase activity in the heart. These data suggest that the Ras/MAP kinase pathway contributes to DOCA-salt-induced hypertension and associated vascular pathology consequent to activation of CYP450.

Alkyl and Aryl Transferases↗
PubMed1999

Discovery and structure-activity relationships of imidazole-containing tetrahydrobenzodiazepine inhibitors of farnesyltransferase.

2,3,4,5-Tetrahydro-1-(imidazol-4-ylalkyl)-1,4-benzodiazepines were found to be potent inhibitors of farnesyltransferase (FT). A hydrophobic substituent at the 4-position of the benzodiazepine, linked via a hydrogen bond acceptor, was important to enzyme inhibitory activity. An aryl ring at position 7 or a hydrophobic group linked to the 8-position through an amide, carbamate, or urea linkage was also important for potent inhibition. 2,3,4, 5-Tetrahydro-1-(1H-imidazol-4-ylmethyl)-7-(4-pyridinyl)-4-[2-(t rifluo romethoxy)benzoyl]-1H-1,4-benzodiazepine (36), with an FT IC(50) value of 24 nM, produced 85% phenotypic reversion of Ras transformed NIH 3T3 cells at 1.25 microM and had an EC(50) of 160 nM for inhibition of anchorage-independent growth in soft agar of H-Ras transformed Rat-1 cells. Selected analogues demonstrated ip antitumor activity against an ip Rat-1 tumor in mice.

3T3 Cells↗
PubMed1996

Potent, cell active, non-thiol tetrapeptide inhibitors of farnesyltransferase.

All previously reported CAAX-based farnesyltransferase inhibitors contain a thiol functionality. We report that attachment of the 4-imidazolyl group, via 1-, 2-, or 3-carbon alkyl or alkanoyl spacers, to Val-Tic-Met or tLeu-Tic-Gln provides potent FT inhibitors. (R*)-N-[[1,2,3,4-Tetrahydro-2-[N-[2-(1H-imidazol-4-yl)ethyl] -L-valyl]-3-isoquinolinyl]carbonyl]-L-methionine ([imidazol- 4-yl-ethyl]-Val-Tic-Met), with FT IC50 = 0.79 nM, displayed potent cell activity in the absence of prodrug formation (SAG EC50 = 3.8 muM).

3T3 Cells↗
PubMed1996

Development of highly potent inhibitors of Ras farnesyltransferase possessing cellular and in vivo activity.

Analogs of CVFM (a known nonsubstrate farnesyltransferase (FT) inhibitor derived from a CA1A2X sequence where C is cysteine, A is an aliphatic residue, and X is any residue) were prepared where phenylalanine was replaced by (Z)-dehydrophenylalanine, 2-aminoindan-2-carboxylate, 1,2,3,4-tetrahydroisoquinoline-3-carboxylate (Tic), and indoline-2-carboxylate. The greatest improvement in FT inhibitory potency was observed for the Tic derivative (IC50 = 1 nM); however, this compound was ineffective in blocking oncogenic Ras-induced transformation of NIH-3T3 fibroblast cells. A compound was prepared in which both the Cys-Val methyleneamine isostere and the Tic replacement were incorporated. This derivative inhibited FT with an IC50 of 0.6 nM and inhibited anchorage-independent growth of stably transformed NIH-3T3 fibroblast cells by 50% at 5 microM. Replacing the A1 side chain of this derivative with a tert-butyl group and replacing the X position with glutamine led to a derivative with an IC50 of 2.8 nM and an EC50 of 0.19 microM, a 26-fold improvement over (S*,R*)-N-[[2-[N-(2-amino-3-mercaptopropyl)-L-valyl]-1,2,3,4- tetrahydro-3-isoquinolinyl]carbonyl]-L-methionine. This derivative, (S*,R*)-N-[[2-[N-(2-amino-3-mercaptopropyl)-L-tert-leucyl]-1,2,3,4 - tetrahydro-3-isoquinolinyl]-carbonyl]-L-glutamine, was evaluated in vivo along with (S*,R*)-N-[[2-[N-(2-amino-3- mercaptopropyl)-L-tert-leucyl]-1,2,3,4-tetrahydro-3- isoquinolinyl]carbonyl]-L-methionine methyl ester for antitumor activity in an athymic mouse model implanted ip with H-ras-transformed rat-1 tumor cells. When administered by injection twice a day at 45 mg/kg for 11 consecutive days, both compounds showed prolonged survival time (T/C = 142-145%), thus demonstrating efficacy against ras oncogene-containing tumors in vivo.

3T3 Cells↗
PubMed1995

Farnesyltransferase inhibitors block the neurofibromatosis type I (NF1) malignant phenotype.

Neurofibromatosis type I (NF1) is a hereditary tumor and developmental disorder whose defective gene was cloned previously. The protein product of the NF1 gene, neurofibromin, contains a domain that shows significant sequence homology to the known catalytic domains of mammalian Ras GTPase-activating proteins (GAP) and the yeast IRA1 and IRA2 proteins. This homologous region of neurofibromin has been shown to exhibit GAP activity toward Ras proteins. Malignant schwannoma cell lines from NF1 patients contain normal levels of GAP and nonmutated Ras proteins but barely detectable levels of neurofibromin, based on genetic mutations in the NF1 gene. Because these cells contain constitutively activated Ras.GTP, it has been proposed that neurofibromin may be the sole negative regulator of Ras in these cells. Overall, these results have implied an important role of the Ras signaling pathway in NF1 malignant schwannomas. Recently, several laboratories have developed small molecule inhibitors of Ras function that inhibit the enzyme farnesyltransferase (FT). FT-mediated post-translational farnesylation of Ras proteins is absolutely necessary for Ras function since this modification is required for the anchoring of Ras proteins to the plasma cell membrane. Although previous studies have shown that FT inhibitors can block the growth of tumor cells carrying mutant Ras proteins, it remained unclear how this class of inhibitors would affect tumor cells such as in NF1, whose malignant growth appears to be mediated by up-regulation of wild-type Ras activity. Thus, in the current study, we investigated whether BMS-186511, a bisubstrate analogue inhibitor of FT, would inhibit the malignant growth properties of a cell line established from malignant schwannoma of an NF1 patient. Our results indicate that the malignant growth properties of ST88-14 cells, the most malignant cell line among several well-characterized NF1 cells, are inhibited by BMS-186511 in a concentration-dependent manner. Following treatment with BMS-186511, ST88-14 cells became flat, nonrefractile, were contact-inhibited, and lost their ability to grow in soft agar. In the drug-exposed cells, Ras proteins were prevented from FT-mediated membrane association. BMS-186511 was found to specifically inhibit FT, but not geranylgeranyltransferase I, a closely related enzyme. Thus, it is conceivable that FT inhibitors may ultimately become the first generation of drugs against the malignant phenotype in NF1 based on rational insights into the mechanism of action of neurofibromin.

Alkyl and Aryl Transferases↗
PubMed1995

Farnesyl diphosphate-based inhibitors of Ras farnesyl protein transferase.

The rational design, synthesis, and biological activity of farnesyl diphosphate (FPP)-based inhibitors of the enzyme Ras farnesyl protein transferase (FPT) is described. Compound 3, wherein a beta-carboxylic phosphonic acid type pyrophosphate (PP) surrogate is connected to the hydrophobic farnesyl group by an amide linker, was found to be a potent (I50(FPT) = 75 nM) and selective inhibitor of FPT, as evidenced by its inferior activity against squalene synthetase (I50(SS) = 516 microM) and mevalonate kinase (I50(MK) = > 200 microM). A systematic structure-activity relationship study involving modifications of the farnesyl group, the amide linker, and the PP surrogate of 3 was undertaken. Both the carboxylic and phosphonic acid groups of the beta-carboxylic phosphonic acid PP surrogate are essential for activity, since deletion of either group results in 50-2600-fold loss in activity (6-9, I50 = 4.6-220 microM). The farnesyl group also displays very stringent requirements and does not tolerate one carbon homologation (12, I50 = 17.7 microM), substitution by a dodecyl fragment (14, I50 = 9 microM), or introduction of an extra methyl group at the allylic position (18, I50 = 55 microM). Modifications around the amide linker group of 3 were more forgiving, as evidenced by the activity of N-methyl analog (21, I50 = 0.53 microM), the one carbon atom shorter farnesoic acid-derived retroamide analog (32, I50 = 250 nM), and the exact retroamide analog (49, I50 = 50 nM). FPP analogs such as 3, 32, and 49 are novel, potent, selective, small-sized, nonpeptidic inhibitors of FPT that may find utility as antitumor agents.

Alkyl and Aryl Transferases↗
PubMed1995

Bisubstrate inhibitors of farnesyltransferase: a novel class of specific inhibitors of ras transformed cells.

We describe the biological properties of a new class of potent farnesyltransferase (FT) inhibitors designed as bisubstrate analog inhibitors. These inhibitors incorporate the structural motifs of both farnesyl pyrophosphate and the CAAX tetrapeptide, the two substrates of the reaction catalyzed by FT. Both the phosphinate inhibitor, BMS-185878, and the phosphonate inhibitor, BMS-184467, exhibited higher in vitro FT selectivity than some of the previously reported CVFM peptidomimentics and benzodiazepine analogs. Xenopus oocyte maturation induced by microinjected oncogenic Ras proteins was blocked by coinjected BMS-184467 and BMS-185878. However, both inhibitors showed poor cell activity presumably because of the doubly charged nature of the compounds. Thus, masking the charge on the carboxylate ion markedly improved the cell permeability of BMS-185878, leading to BMS-186511, the methyl carboxyl ester prodrug. BMS-186511 inhibited FT activity in whole cells as determined by inhibition of p21 Ras protein processing, inhibition of farnesylation of proteins including Ras and the accumulation of unfarnesylated Ras proteins in the cytosolic fraction. While the cellular effects of these bisubstrate analog inhibitors had no significant effect on growth of untransformed NIH3T3 cells, they produced pronounced inhibition of Ras transformed cell growth. Both the anchorage dependent and independent growth of ras transformed cells were severely curtailed by micromolar concentrations of BMS-186511. We also found that both H-ras and K-ras transformed cells are affected by this bisubstrate inhibitor. However, K-ras transformed cells appear to be less sensitive. The inhibition of FT activity in cells and the ensuing inhibition of ras transformed cell growth is further manifested in distinct morphological changes in cells. Cells flattened, became less refractile and grew in contact inhibited monolayer. Moreover, the highly diffused character of the actin cytoskeleton in the ras transformed cells was dramatically reverted to an organized network of stress cables crisscrossing the entire cells upon treatment with BMS-186511. All of these effects of BMS-186511 are limited to ras transformed cells that utilize farnesylated Ras, but are not seen in transformed cells that use geranylgeranyl Ras or myristoyl Ras. Significantly, these FT inhibitors did not produce any signs of gross cytotoxicity in untransformed, ras transformed cells or other oncogene transformed cells.

3T3 Cells↗
PubMed1994

Farnesylation of p21 Ras proteins in Xenopus oocytes.

Unprocessed p21 Ras proteins microinjected into Xenopus oocytes were radiolabeled by coinjected [3H]farnesyl pyrophosphate, a direct farnesyl donor substrate for all known mammalian farnesyltransferases. Mevinolin, an inhibitor of HMG CoA reductase which reduces the levels of mevalonate and thus farnesyl pyrophosphate, blocked oncogenic H-Rasva112 induced germinal vesicle breakdown in oocytes. This mevinolin caused block was completely reversed by co-injected farnesyl pyrophosphate. The putative farnesyltransferase in Xenopus oocytes was identified to be similar to those found in mammalian cells in that it requires an intact CAAX box motif in addition to the conserved cysteine residue at the fourth position from the C-terminus of Ras proteins for its farnesylating activity. Peptide inhibitors of farnesyltransferase such as CVIM and TKCVIM were shown to inhibit farnesylation of microinjected Ras proteins thereby blocking its function namely the induction of oocyte maturation. These results demonstrate that Xenopus oocytes process bacterially produced mammalian Ras proteins in a manner similar to, if not identical with that in mammalian cells, thus validating the continued use of the Xenopus oocyte system for unraveling the functions of Ras proteins. Furthermore, our results indicate that the oocyte system may be a useful in vivo model for studying the farnesylation of human Ras proteins, its regulation, and the effects of farnesyltransferase inhibitors.

Alkyl and Aryl Transferases↗
PubMed1993

Purified yeast protein farnesyltransferase is structurally and functionally similar to its mammalian counterpart.

Protein farnesyltransferase (FTase) catalyses the addition of a farnesyl group to a cysteine within the so-called 'CAAX box' at the C-terminus of various proteins. In the present paper we report purification of Saccharomyces cerevisiae FTase to near-homogeneity. This was accomplished by constructing a yeast strain overproducing FTase approx. 100-fold. The purified enzyme was a heterodimer of approx. 90 kDa and consisted of 43 kDa and 34 kDa subunits. The 43 kDa subunit was shown to be the product of the DPR1 gene by using antibody raised against baculovirus-produced DPR1 polypeptide. The purified enzyme required Mg2+, showed a pH optimum of 7.8 and was most active at 50 degrees C. The Km values for farnesyl pyrophosphate and GST-CIIS (glutathione S-transferase fused to the C-terminal 12 amino acids of yeast RAS2 protein), KmFpp and KmGST CIIS, were 8.1 and 5.1 microM respectively. The enzyme was capable of farnesylating GST-CIIL (the same as GST-CIIS, except that the C-terminal serine is changed to leucine), a substrate protein for the enzyme geranylgeranyltransferase, although with a higher apparent Km than for GST-CIIS. Like its mammalian counterpart, yeast FTase activity was inhibited by peptides containing the C-terminal CAAX sequence (that is, one where C = cysteine, A = aliphatic amino acid and X = any amino acid). These results provide direct evidence for the idea that the yeast and mammalian FTases are structurally and functionally very similar.

Alkyl and Aryl Transferases↗
PubMed1992

10'-Desmethoxystreptonigrin, a novel analog of streptonigrin.

10'-Desmethoxystreptonigrin, a novel analog of streptonigrin produced by Streptomyces albus, was discovered in a screen for inhibitors of farnesylation of RAS p21 protein. The compound was isolated from the fermentation broth and its structure determined. It is markedly cytotoxic to several human tumor cell lines and also exhibits potent broad-spectrum antibacterial activity.

Animals↗
PubMed1990

Identification and preliminary characterization of protein-cysteine farnesyltransferase.

Ras proteins must be isoprenylated at a conserved cysteine residue near the carboxyl terminus (Cys-186 in mammalian Ras p21 proteins) in order to exert their biological activity. Previous studies indicate that an intermediate in the mevalonate pathway, most likely farnesyl pyrophosphate, is the donor of this isoprenyl group. Inhibition of mevalonate synthesis reverts the abnormal phenotypes induced by the mutant RAS2Val-19 gene in Saccharomyces cerevisiae and blocks the maturation of Xenopus oocytes induced by an oncogenic Ras p21 protein of human origin. These results have raised the possibility of using inhibitors of the mevalonate pathway to block the transforming properties of ras oncogenes. Unfortunately, mevalonate is a precursor of various end products essential to mammalian cells, such as dolichols, ubiquinones, heme A, and cholesterol. In this study, we describe an enzymatic activity(ies) capable of catalyzing the farnesylation of unprocessed Ras p21 proteins in vitro at the correct (Cys-186) residue. This farnesylating activity is heat-labile, requires Mg2+ or Mn2+ ions, is linear with time and with enzyme concentration, and is present in all mammalian cell lines and tissues tested. Gel filtration analysis of a partially purified preparation of protein farnesyltransferase revealed two peaks of activity at 250-350 kDa and 80-130 kDa. Availability of an in vitro protein farnesyltransferase assay should be useful in screening for potential inhibitors of ras oncogene function that will not interfere with other aspects of the mevalonate pathway.

Alkyl and Aryl Transferases↗
PubMed1988

A novel candidate for receptor-coupled phospholipase C purified from human platelets.

The breakdown of polyphosphoinositides (PPI) but not phosphatidylinositol (PI) has been hypothesized as the primary event following agonist (hormones/growth factors/neurotransmitters) stimulation in a wide variety of systems. This, in turn, predicts the existence of a phospholipase C (PLC) enzyme that shows specificity to PPI. Ideally, this PPI-specific PLC activity should not be absolutely dependent on Ca2+ because of its proposed role in Ca2+ mobilization. I have recently identified two PLC activities that are specific to PPI and have described their resolution from a PLC that acts on all three phosphoinositides (Manne, 1987). In this report, I describe purification to near homogeneity of one of these PLC activities. The enzyme shows maximal activity towards PPI in the presence of physiological Mg2+ concentrations, and does not act on PI under conditions optimal for PPI hydrolysis. However, a weak PI hydrolytic activity, representing about 1/8th to 1/20th of that observed with PPI is detected when 0-100 microM Ca2+ is present in the assay. This weak PI hydrolytic activity is strongly inhibited by mM Ca2+, which is required at mM levels for most of the PLC enzymes described in literature. The size of the native enzyme as determined by gel filtration (high performance liquid chromatography) is 140 kDa. Analysis of the purified enzyme by HPLC on Zorbax GF-250 column showed a single major peak that coincided with the enzyme activity. Under both denaturing and non-denaturing conditions of SDS-polyacrylamide gel electrophoresis, the highly purified enzyme shows two major bands of 38 kDa and 42 kDa, which together represent about 90% of the total stain on the gel.

Blood Platelets↗
PubMed1987

Characterization of phosphoinositide-specific phospholipase C from human platelets.

Phosphoinositide-specific phospholipase C (PI-PLC) from human platelet cytosol was purified 190-fold to a specific activity of 0.68 mumol of phosphatidylinositol (PI) cleaved/min per mg of protein. It hydrolyses PI and phosphatidylinositol 4,5-bisphosphate (PIP2), but not phosphatidylcholine, phosphatidylserine or phosphatidylethanolamine. The enzyme exhibits an acid pH optimum of 5.5 and has a molecular mass of 98 kDa as determined by Sephacryl S-200 gel filtration. It required millimolar concentrations of Ca2+ for PI hydrolysis, whereas micromolar concentrations are optimal for PIP2 hydrolysis. Mg2+ could substitute for Ca2+ when PIP2, but not PI, was used as the substrate. EDTA was more effective than EGTA in inhibiting the basal PI-PLC activity towards PIP2. Sodium deoxycholate strongly inhibits the purified PI-PLC activity with either PI or PIP2 as substrate. Ras proteins, either alone or in the form of liposomes, have no effect on PI-PLC activity.

Blood Platelets↗
PubMed1987

Identification of polyphosphoinositide-specific phospholipase C and its resolution from phosphoinositide-specific phospholipase C from human platelet extract.

Sonicated platelet extract, obtained after high-speed centrifugation, was fractionated by phosphocellulose chromatography, and assayed for phosphodiesteric cleavage of phosphatidylinositol (PI), phosphatidylinositol 4-phosphate (PIP) and phosphatidylinositol 4,5-biphosphate (PIP2) using (i) single bilayer vesicles from total platelet membrane lipids and (ii) single bilayer vesicles from individual pure lipids. When total platelet lipids were used as the substrate, two clear-cut, but incompletely resolved, peaks of phosphoinositide-specific phospholipase C (PI-PLC) were detected; one of these activities hydrolysed PIP alone, whereas the second peak hydrolysed all three phosphoinositides. When pure phosphoinositides were used as the substrate, three distinct peaks of PI-PLC were observed; two of these peak activities correspond to the peaks when assays were conducted with total platelet membrane lipids. The third peak of activity hydrolysed PIP2 and PIP, but not PI. These results clearly show that there exist PIP/PIP2-specific PLC enzymes that do not act on PI, and escaped detection thus far because of the general practice of using PI as the substrate to monitor PI-PLC activities. I propose that these PIP/PIP2-specific PLC enzymes are the real candidates that respond to agonist occupation of receptors on the cell surface to generate the two putative second messengers inositol triphosphate and diacylglycerol.

Blood Platelets↗