Neurochemical analysis of the tyrosine hydroxylase expression in methamphetamine-sensitized rats

To elucidate the expression of TH mRNA in MAP-induced behavioral sensitization, rats were daily injected with MAP (5 mg/kg i.p.) or saline for 14 days. Progressive enhancement was observed in MAP-induced stereotyped behavior. After 7 days of discontinuation of MAP treatment, the rats were decapitated and the brains were prepared for either in situ hybridization or Northern blot hybridization. In situ hybridization revealed that the signals of TH mRNA were localized to the dopaminergic perikarya of substantia nigra and ventral tegmental area in the midbrain, and Northern blot analysis showed that the levels of TH mRNA in these areas decreased by 37% compared to that in the saline-treated controls. These findings indicate that MAP-induced dopaminergic hyperactivity is not associated with enhanced expression of TH gene mRNA.

Familial Alzheimer's disease-linked mutations at Val717 of amyloid precursor protein are specific for the increased secretion of A beta 42(43)

In some pedigrees of familial Alzheimer's disease (FAD), three mutations of beta amyloid precursor protein (APP) have been found at the Val717 residue (to Ile, Phe, or Cly) and these mutations increase the secretion of A beta 42(43). To study the specificity of the effects of these mutations on APP processing, we transiently expressed APP genes with mutations of Val717 to Lys, Ser, Glu, or Cys in COS cells. The three familial AD-linked mutations increased the levels or ratios of A beta 42(43), whereas the secretion of A beta 40 was decreased. Other mutations irrelevant to FAD except Val717 to Lys had little effect on the ratio of A beta 42(43). Substitution to Lys decreased the secretion of A beta 42(43); substitution to Glu or Gly decreased the amount of intracellular C-terminal fragment produced by alpha-secretase, whereas it was increased by mutations to Phe, Cys, or Lys. However, the levels of secretion of soluble APP were constant, but a substitution to Glu reduced it. These results suggest a specific role of the Val717 residue in APP processing and, especially, in gamma-cleavage.

Primary adenocarcinoma of the renal pelvis with special reference to histochemical observations

A case of adenocarcinoma of the renal pelvis is presented. The patient was an 84-year-old man suffering from long-standing right-sided nephrolithiasis. Surgical resection of the right kidney revealed adenocarcinoma with slight stromal invasion. A tubulovillous adenoma, which was morphologically similar to an adenoma of the large intestine, was also found adjacent to the adenocarcinoma. The pelvic epithelium neighboring the lesion revealed intestinal metaplasia. Histochemical studies revealed that the tumor in the patient and adenocarcinomas or adenomas of the large intestine have similar properties of cytoplasmic mucin. These findings suggest that the epithelium with intestinal metaplasia may have developed into the adenoma and finally transformed into the adenocarcinoma. In addition, only tumor cells with severe atypia, most of which morphologically corresponded to adenocarcinoma, demonstrated positive nuclear staining for anti-p53. This suggests that p53 may play an important role in the malignant transformation of adenomas into adenocarcinomas, as is the case in the large intestine.

Effects of indomethacin on the production of matrix metalloproteinase-3 and tissue inhibitor of metalloproteinases-1 by human articular chondrocytes

OBJECTIVE

To study the action of indomethacin on cartilage catabolic activity by comparing the production of a matrix degrading proteinase and its inhibitor in human articular chondrocyte cultures.

METHODS

Matrix metalloproteinase-3 (MMP-3) and tissue inhibitor of metalloproteinases-1 (TIMP-1) in conditioned medium from human articular chondrocyte cultures were measured using a one-step sandwich enzyme immunoassay. TIMP-1 mRNA expression was analyzed by Northern blotting using a 0.6 kb cDNA probe for human TIMP-1.

RESULTS

Human recombinant interleukin 1 beta (IL-1 beta) increased MMP-3 levels in primary chondrocyte cultures. Indomethacin at 10(-5) M inhibited this IL-1 beta stimulation, but had no effect in the therapeutic range (10(-6)-10(-7) M). Low levels of indomethacin (10(-7) M) significantly increased the production of TIMP-1 by chondrocytes. Synthesis of TIMP-1 appeared to be inhibited by prostaglandin E2 (PGE2), since exogenously added PGE2 reversed the stimulating effect of indomethacin on TIMP-1 production. Northern blot analysis showed that 10(-7) M indomethacin increased TIMP-1 mRNA levels in chondrocytes.

CONCLUSION

Our findings indicate that low levels of indomethacin can benefit matrix metabolism by affecting the balance of proteinases to their inhibitors in human articular cartilage.

The prognostic significance of vascular invasion by endometrial carcinoma

BACKGROUND

Recently, invasion of vascular spaces by endometrial carcinoma has received particular attention as a prognostic factor. The goal of the current investigation was to re-examine the effect of vascular invasion on tumor recurrence and survival in patients with endometrial carcinoma.

METHODS

Surgical specimens from 238 patients with endometrial carcinoma were examined for the presence of vascular invasion by tumor cells. Vascular invasion was compared with clinicopathologic features and postoperative survival. Survival curves by vascular invasion were evaluated by the Kaplan-Meier method.

RESULTS

In a histopathologic review of 238 cases of endometrial carcinoma, 82 neoplasms demonstrated vascular invasion. Vascular invasion significantly correlated with the extension of primary tumor, depth of myometrial invasion, and histologic grade. Patients with lymph node metastasis had a significantly higher incidence of vascular invasion. Survival at 5 years for patients with vascular invasion was 73.4%. This was significantly lower than the survival rate of 91.5% for women without this finding (P < 0.001). Among patients with lymph node metastasis, 80.2% of the patients with vascular invasion survived for 5 years compared with 95.3% of the patients without vascular invasion (P < 0.05). Ten of 47 patients with no lymph node metastasis but with vascular invasion developed recurrent carcinoma. Nine of these ten patients apparently had extrapelvic recurrences.

CONCLUSIONS

The presence of vascular invasion is a reliable prognostic indicator. Recording of tumor recurrence pattern may lead to a better selection of patients for adjuvant systemic therapy after surgery.

Pre-operative time course changes in liver function tests in biliary atresia: its usefulness in the discrimination of biliary atresia in early infancy

In order to investigate the possibility of early discrimination of extrahepatic biliary atresia from other cholestatic diseases, a series of results of liver function tests in infants with cholestatic diseases were reviewed. The results of routine liver function tests (LFT) recorded in patients' charts were reviewed within 12 weeks after birth in 47 infants with extrahepatic biliary atresia (BA), 10 infants with neonatal hepatitis (NH) and 130 age-matched control infants (CO) without cholestatic diseases. The mean of each test value for each week after birth was derived from the actual data examined in each infant. No differences were observed between BA and CO in the levels of aminotransferases within 2 weeks after birth. Total bilirubin and direct bilirubin levels were significantly different between BA and CO within 1 week after birth (16.1 +/- 3.2 mg/dL vs 11.1 +/- 4.5 mg/dL, 4.6 +/- 2.6 mg/dL vs 0.7 +/- 0.3 mg/dL, respectively). The direct bilirubin-total bilirubin ratio exceeded 25% within the first week in BA. The individual values of direct bilirubin (DB) exceeded 2 mg/dL within the first week in all infants with BA, while none of the individual values exceeded 1.6 mg/dL in CO. Gamma-glutamyl transpeptidase levels were significantly different between BA and CO at 4 weeks (432 +/- 272 IU/L vs 79 +/- 43 IU/L) and thereafter; and were significantly different between BA and NH at 6 weeks (314 +/- 232 IU/I vs 69 +/- 58 IU/L) and thereafter. These data suggest that the determination of direct bilirubin within 1 week after birth can detect extrahepatic biliary atresia patients from those with physiologic jaundice, and gamma-glutamyl transpeptidase levels may discriminate BA from NH at no later than 6 weeks of age.

Determination of stromelysin-1, 72 and 92 kDa type IV collagenase, tissue inhibitor of metalloproteinase-1 (TIMP-1), and TIMP-2 in synovial fluid and serum from patients with rheumatoid arthritis

OBJECTIVE

To investigate the correlation between serum and synovial fluid (SF) concentrations of stromelysin-1 (MMP-3), gelatinases (MMP-2 and MMP-9), tissue inhibitors of metalloproteinases (TIMP-1 and TIMP-2) in patients with rheumatoid arthritis (RA) and to assess the role of these proteins in cartilage destruction and their clinical value as indicators of disease activity.

METHODS

Enzyme linked immunoassays (ELISA) were used. SF and serum samples were collected simultaneously from 55 patients with RA. Radiographic (Larsen grade) and clinical evaluations were also done.

RESULTS

There was significant correlation between SF concentrations of MMP-3 and MMP-9. In addition, there was significant negative correlation between SF concentrations of TIMP-2 and MMP-2, 3, and 9. The only correlation observed among MMP and TIMP in serum was that of MMP-3 with MMP-2. Significant correlation was also found between MMP-3 concentrations in the serum and SF. There were no significant correlations between radiological grade and concentrations of these proteins. Patients with mild to moderate functional disability showed significantly higher serum TIMP-1 concentrations than patients with severe disability.

CONCLUSION

Extremely high concentrations of MMP-3 in SF of the patients with RA may contribute to its elevation in serum. It would seem that regulation of TIMP production depends upon the disease state and not the concentration of MMP. Discrepancies between concentrations of TIMP and MMP in SF may be responsible for cartilage destruction in RA.

Ca2+/calmodulin-dependent protein kinase II in septally kindled rat brains: changes in protein level, activity and subcellular distribution in hippocampus and cerebral cortex

The protein level and the activity of Ca2+/calmodulin-dependent protein kinase II (CaM kinase II) in homogenate from septally kindled rat brains were quantitatively compared with those from paired controls 2 weeks after the final stimulation. The major alpha subunit level was decreased, while the activity was increased in crude homogenate from hippocampus and parietal cortex of kindled animals, indicating an apparent increase in the specific activity of CaM kinase II in these regions of the kindled brains. No such changes were observed in cerebellum. After the separation of crude homogenate into the soluble and particulate fractions, the ratio of CaM kinase II activity recovered in the soluble fraction was increased in hippocampus and parietal cortex, indicating a change in subcellular distribution of CaM kinase II in the kindled state.

Early definitive surgery for total colon aganglionosis: Duhamel procedure with right colon patch graft using GIA stapler

A report is presented of an infant with total colon aganglionosis (TCA) with ileal involvement in whom a modified Duhamel procedure was used accompanied by a right colon patch graft 12 cm in length using a GIA-90 stapler at 3 months of age. The patient with TCA is usually treated by an initial diverting ileostomy followed by a definitive operation performed several months later. However, the management during the ileostomy period is associated with a variety of problems. In to minimize the resulting complications, we developed a procedure to allow a much earlier definitive operation.

Major risk factors for atherosclerosis are manifested in experimental Ca-deficiency

The eggshell is the major source of Ca required during growth of chick embryos. Therefore, chick embryos placed ex ovo for long-term (SL) are rendered severe systemic calcium deficiency. We report here that SL chick embryos express Ca-deficiency related atherogenic disorders, and that in vitro Ca-deficiency induces dedifferentiation, i.e. loss of cell-type specific features and accelerated proliferative activities, in the various types of cultured cells. Systemic blood pressure is significantly higher and an accelerated weight gain of the heart is noted in SL compared to normal embryos (NL) at the incubation Day-14. Plasma cholesterol was lower, while triglyceride and glucose were higher in SL. Varying Ca in the culture medium (FCa, 1.8 mM; HCa, 2.8 mM; Ca/2, 0.9 mM) clearly affected the phenotype of the cultured cardiomyocytes and vascular cells isolated from the chick embryos. The cell number and total DNA were significantly larger and the level of LDH and proliferating cell nuclear antigen (PCNA) was elevated in Ca/2 compared to FCa. On the contrary, the level of CPK and contractile proteins were lowered in Ca/2. Thus, it is indicated that Ca-deficiency induces atherogenic disorders in vivo, and accelerates cell proliferation and decelerates sarcomeric protein expression in vitro. Taken together, it is suggested that the atherogenic, developmental disorders in SL may be the integrated result of the phenotype alteration in the various cell types directly induced by Ca-deficiency.

Molecular cloning of a novel basic helix-loop-helix protein from the rat brain

In the mammalian nervous system, several basic helix-loop-helix (bHLH) proteins have been identified that may play essential roles in neurogenesis or neural development. This paper describes a novel bHLH protein in rat brain, which has a bHLH domain highly homologous with that of MATH-2 and NeuroD. On the other hand, the amino-acid sequence of the other regions had little homology with those of the known proteins. This protein consists of 381 amino acids and was detected only in neural tissue, indicating that it has an important role specific to neuronal activities.

A case of prenatally detected bilateral paraureteral diverticula associated with neurofibromatosis

Although paraureteral diverticulum is thought to be a congenital anomaly, no prenatally detected cases have been reported. Herein, we report a case of bilateral paraureteral diverticula prenatally detected by maternal ultrasonography. This case also had dysplastic kidneys in association with neurofibromatosis.

Evaluation of human skin irritation by carboxylic acids, alcohols, esters and aldehydes, with nitrocellulose-replica method and closed patch testing

Closed patch testing and the nitrocellulose-replica method are performed as useful clinical methods for the evaluation of human skin irritation by cosmetics and topical medicaments. Comparison of the sensitivity between microscopic scoring by nitrocellulose-replica method and visual scoring by closed patch test in the detection of skin irritation, however, has not been well studied with statistical analysis. Here, we evaluated human skin irritation by carboxylic acids, alcohols, esters and aldehydes, with different chain length (C8-C18), using both methods. The results of closed patch testing showed that, although the score of skin irritation for carboxylic acids (C8, C12), alcohols (C8) and aldehydes (C8), tested at a concentration of 0.5 m-2.0 m, significantly increased with increasing concentration of the test compounds, ester compounds scarcely caused any irritation on the surface of the skin occluded. In addition, an increase of carbon chain length in the test compounds made it impossible to detect skin irritation. In contrast, the nitrocellulose-replica method could evaluate skin reactions against very weak irritants that gave no macroscopic alterations on the skin surface in the closed patch test. However, the scoring system is somewhat subjective and should be improved to make the analysis more objective.

Isolation and characterization of the IS3-like element from Thermus aquaticus

We have cloned and characterized a genetic element (1187 bp) that is responsible for the induction of thermotolerance as well as ompC expression in E. coli. This element (ISLtaq1) was isolated from Thermus aquaticus. DNA and protein data bases were searched with this element (ISLtaq1), which suggested it to be very similar to IS150 belonging to the IS3 family. ORF1, found on ISLtaq1, which encodes 100 amino acids (aa), had a DNA-binding motif: a helix-turn-helix and a leucine zipper. In fact, when the ORF1 protein was overproduced in E. coli, thermotolerance as well as ompC expression was induced.

Levels of circulating collagenase, stromelysin-1, and tissue inhibitor of matrix metalloproteinases 1 in patients with rheumatoid arthritis. Relationship to serum levels of antigenic keratan sulfate and systemic parameters of inflammation

OBJECTIVE

To measure serum levels of matrix metalloproteinase-1 (MMP-1), matrix metalloproteinase-3 (MMP-3), and tissue inhibitor of MMP-1 (TIMP-1) in patients with rheumatoid arthritis (RA) and in age-matched control subjects, and to determine how these correlate with serum levels of antigenic keratan sulfate (KS) and other biochemical and clinical indicators of disease activity.

METHODS

Immunoassays were used to measure levels of MMP-1, MMP-3, TIMP-1, and antigenic KS. Radiologic and functional joint scores were based upon Steinbrocker's criteria. Erythrocyte sedimentation rates (ESR) and levels of C-reactive proteins (CRP) were measured.

RESULTS

In RA patients, levels of MMP-3 and TIMP-1 were significantly increased, and strongly correlated with the ESR and CRP levels but not with radiologic or functional joint scores. Levels of antigenic KS were significantly lower in RA patients and correlated negatively with systemic parameters of inflammation and serum levels of TIMP-1.

CONCLUSIONS

The increase in serum levels of MMP-3 and TIMP-1 appears to reflect systemic inflammation in RA. The inverse correlation between serum levels of TIMP-1 and antigenic KS suggests that an upregulation of TIMP-1 synthesis might be responsible for the apparent suppression of cartilage aggrecan catabolism in patients with severe inflammatory changes.

Increased levels of stromelysin-1 and tissue inhibitor of metalloproteinases-1 in sera from patients with rheumatoid arthritis

OBJECTIVE

To evaluate the efficacy of stromelysin-1 (matrix metalloproteinase-3 [MMP-3]) and tissue inhibitor of metalloproteinases-1 (TIMP-1) in serum as markers for joint inflammation in rheumatoid arthritis (RA).

METHODS

Levels of both macromolecules in sera from 97 healthy controls, 109 patients with RA, and 47 patients with osteoarthritis (OA) were measured by respective 1-step sandwich enzyme immunoassays. In the patients with RA, serum levels of MMP-3 and TIMP-1 were investigated in relation to laboratory and clinical measures of disease activity. In addition, the relationships between serum and synovial fluid (SF) levels in paired samples from individual patients were examined.

RESULTS

Serum levels of both MMP-3 and TIMP-1 in RA patients were significantly higher than those in OA patients and in healthy controls (P < 0.001), and were shown to correlate with traditional systemic markers of inflammation including the erythrocyte sedimentation rate and C-reactive protein level, and with the Lansbury articular index. In addition, it was noted that serum levels of MMP-3 correlated with the corresponding values in paired SF samples obtained concurrently from patients with RA (rs = 0.588, P < 0.001), while such correlations were not found for TIMP-1 levels.

CONCLUSION

Our results support the notion that levels of both MMP-3 and TIMP-1 in RA patient sera are increased in association with inflammation. Furthermore, the level of MMP-3 in serum provides a particularly useful marker of inflammatory activity in the joints of patients with RA.

Cloning and sequence analysis of cDNA for a possible DNA-binding protein 5E5 in the nervous system

Monoclonal antibody 5E5 recognized an intranuclear antigen of neurons in the rat. We isolated 5E5cDNA and determined its nucleotide and deduced amino acid sequences. The 5E5cDNA had an open reading frame of 825 amino acids and its amino acid sequence showed no significant homology to any protein or to any DNA binding motif so far known. 5E5 protein had an abundance of basic amino acids, especially arginine, and included a glycine-rich region and a proline cluster. Monoclonal antibody 12H raised against 5E5cDNA fusion protein recognized an intranuclear substance in rat brain sections and a single protein band of about 98 kDa in the brain nuclear extract fraction on immunoblotting. DNA-cellulose column chromatography indicated that 5E5 protein might have DNA-binding ability. Transfection studies indicated that 5E5 protein expressed in COS-1 is localized in cell nuclei. These results suggest that 5E5 protein is a possible DNA-binding protein which is expressed especially in neurons.

Methamphetamine-induced dopaminergic hyperactivity is not accompanied with increase in tyrosine hydroxylase mRNA of the rat midbrain

Tyrosine hydroxylase (TH) mRNA was measured in the midbrain of rats treated repeatedly with methamphetamine (MAP). Male Sprague-Dawley rats were daily injected with MAP (5 mg/kg, i.p., once daily) or saline for 14 days. Progressive augmentation was observed in MAP-induced stereotyped behaviors. After one week of abstinence, the rats were decapitated and the brains were prepared for either in situ hybridization using non-radioactive cRNA probes or Northern blot analysis using 32P-labeled cDNA probes. In situ hybridization showed that the signals of TH mRNA were localized to the dopaminergic perikarya in the midbrain and were reduced in MAP-treated animals compared to the controls. Northern blot analysis revealed that the level of TH mRNA in the midbrain of MAP-treated rats was decreased by 37% compared to the controls, which was close to the statistical significance (P = 0.053). These results indicate that the dopaminergic hyperactivity caused by repeated MAP treatment is not associated with enhanced transcription of the TH gene.

Urinary detection of type IV collagen and its increase in glomerulonephritis

Type IV collagen is the major component of the glomerular extracellular matrix. The nature of type IV collagen antigens in the urine from various forms of glomerulonephritis was studied using enzyme-linked immunosorbent assay for monoclonal antibodies to the 7S domain and some of the non-7S and non-NC1 domains. The size distribution of antigenic material in urinary samples from a patient with IgA nephropathy was analyzed by gel filtration chromatography. The results demonstrated a single peak at 340 kDa, suggesting the measurement of almost intact type IV collagen molecules. The urinary concentration of type IV collagen in patients with membranous nephropathy and chronic renal failure was significantly increased compared with that of normal controls. Measurement of the urinary concentrations of type IV collagen is useful in the diagnosis of glomerular disease, particularly in cases where invasive methods are contraindicated and clinically membranous nephropathy is suspected.

A synaptic vesicle-associated protein (SVP-38) as an early indicator of delayed neuronal death

Sixteen gerbils were subjected to 5 min of forebrain ischemia. Their brains were processed for immunohistochemical staining using monoclonal antibodies against a synaptic vesicle-associated protein 38 (SVP-38) and microtubule-associated protein 2 (MAP2) after recirculation times of 10 min, and 1, 4, and 7 days. After 10 min recirculation, SVP-38 immunoreactive dots were observed only in the CA1 region of the hippocampus. After 1 day recirculation, SVP-38 immunostaining was diffuse and weak throughout the hippocampus, despite preservation of MAP2 immunoreactivity. After 4 and 7 days recirculation, SVP-38 immunoreactivity had been restored in the whole hippocampus, despite the complete loss of MAP2 immunoreactivity due to delayed neuronal death. Our results demonstrate an immediate and significant change in the immunoreactivity of a synaptic vesicle-associated protein at the beginning of the process of delayed neuronal death. Thus, changes in the immunoreactivity of synaptic vesicle-associated proteins such as SVP-38 appear to be one of the earliest indicators of the onset of neuronal death.

Secretion of Alzheimer beta/A4 protein (1-40) and intracellular retention of beta/A4 protein (1-42) in transfected COS cells

The amyloid beta/A4 protein (beta/A4) of Alzheimer disease is heterogeneous. A beta 1-40 (Asp1 to Val40) is rather soluble, whereas A beta 1-42 (Asp1 to Ala42) is more insoluble and can be the seed of deposition of A beta 1-40. Although beta/A4 itself could not be expressed transiently in COS cells by cDNA transfection, it was expressed after directly adding a signal sequence to its N-terminal end. The expressed A beta 1-40 was secreted, whereas A beta 1-42 was hardly secreted. A beta 1-40 secretion was not inhibited by metabolic inhibitors such as brefeldin A. The normally produced A beta 1-40 could not be retained intracellularly, whereas the abnormally generated A beta 1-42 might be accumulated intracellularly, resulting in cellular toxicity.

[Stromelysin-1 (MMP-3) level in the sera from patients with rheumatoid arthritis and other connective tissue diseases--clinical significances in early onset rheumatoid arthritis]

Stromelysin-1 (MMP-3) is a metalloproteinase that degrades articular cartilage matrix in patients with rheumatoid arthritis (RA). We measured MMP-3 in the sera from patients with RA and other connective tissue diseases using specific sandwich EIA and studied its clinical significance in early onset RA. MMP-3 level in healthy control (n = 170) was significantly higher in male than in female. The level of MMP-3 in RA was significantly and dramatically higher than in healthy control, osteoarthritis, systemic lupus erythematosus, progressive systemic sclerosis, primary sjogren's syndrome, mixed connective tissue disease, gouty arthritis and traumatic arthritis. Serum MMP-3 significantly correlated with serum BUN or serum creatinine levels in SLE patients but not in RA patients. In early onset RA, serum MMP-3 level was significantly elevated. Furthermore, when the relationship between the serum MMP-3 level and X-ray findings of the joints in RA was studied, it was found that MMP-3 level was elevated even in stage I or II and that there was no statistical differences between stage I or II and stage III or IV, suggesting that serum MMP-3 level is elevated in the early stage of initial inflammatory process when only mild cartilage degradation is seen. These results suggest that measurements of serum MMP-3 is an important tool for establishing diagnosis of early onset RA, and that serum MMP-3 level may be a marker of cartilage destruction and of estimating therapeutic efficacy in early onset RA.

Coordinate regulation of matrix metalloproteases and tissue inhibitor of metalloproteinase expression in human synovial fibroblasts

We examined the common signal transduction mechanisms governing collagenase (MMP-1), stromelysin-1 (MMP-3), and tissue inhibitor of metalloproteases (TIMP-1) gene expression in human synovial fibroblasts for insight into the pathophysiology of arthritis. MMP-1, MMP-3, and TIMP-1 expression and synthesis were induced in cultured human synoviocytes with recombinant human interleukin 1 beta in the absence or presence of either chemical inhibitors of protein kinase A and C (PKA, PKC), or prostaglandin E2, or cyclic AMP (cAMP) mimetics. We used enzyme immunoassays (EIA) to determine MMP-1, MMP-3, and TIMP-1 antigen levels in spent culture medium and Northern hybridization to measure steady state mRNA expression levels. Extracellular signals (e.g., IL-1, phorbol myristic acetate) that result in the activation of cytoplasmic PKC augment in tandem the expression and synthesis of MMP-1, MMP-3, and TIMP-1 in human synovial fibroblasts. In addition, such signals induce nuclear transcription factors (e.g., activator protein 1) that bind to common gene regulatory elements and augment promoter activity of MMP-1, MMP-3, and TIMP-1 gene promoter constructs. In contrast, signals that activate PKA oppose PKC mediated signals, in that the expression of MMP-1, MMP-3, and TIMP-1 are suppressed. Experimental data suggest that the expression of MMP-1, MMP-3, and TIMP-1 are coordinated through a series of common cytoplasmic signal transducing pathways, cis regulatory elements, and nuclear trans acting factors.