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PubMed1985

The role of the kidney in the elimination of pancreatic lipase and amylase from blood.

Two clinical observations indicate that the kidney plays the main role in the elimination of lipase and amylase from the circulation: 1. in patients with uncomplicated acute pancreatitis the decrease of the activity of both enzymes in the serum ran almost in parallel. The half life for lipase was found to be 6.9-13.7 h, and somewhat higher figures (9.3-17.7 h) were calculated for amylase; 2. in patients with reduced glomerular filtration rate the serum activity of either or of both enzymes was distinctly elevated. The contribution of the kidney to the elimination of lipase and amylase from blood was studied in the rat. After an intravenous bolus injection of homologous lipase and amylase, the serum activity of both enzymes decreased rapidly. The half-life of lipase was 18.1 min, that of amylase 20.5 min. Up to 30% of the injected amylase but only traces of lipase activity were recovered in the urine. In animals with ligated kidneys the serum half-life of both enzymes was 3 times longer. Our results indicate that lipase as well as amylase are removed from the serum mainly by glomerular filtration at nearly the same rate. Reabsorption of lipase is almost complete, in contrast to that of amylase. It is suggested that the differences in the renal handling of both enzymes are due to their differing affinities for hydrophilic and hydrophobic surfaces.

Acute Disease↗
PubMed1988

Renal handling of 125I-labelled homologous pancreatic lipase and amylase in the rat.

Experiments were carried out in vivo on rats and in vitro on tubular brush border vesicles in order to study the renal mechanisms of the elimination of pancreatic lipase and amylase from the circulation. Highly purified 125I-labelled homologous lipase, amylase or 125I-labelled di-iodo-tyrosine was injected intravenously in a single dose. The sieving coefficients of lipase and amylase were found to be 0.126 and 0.118 respectively. Less than 1% of the lipase activity but more than 10% of the radioactivity were found in the urine in the course of a 120 min experiment. In experiments with amylase, 16% of the enzyme activity and 19% of the radioactivity were present in the urine. Elimination of both enzymes showed first order kinetics and was of the same magnitude (17-24 min). The elimination curves of the radioactivity consisted of at least two components: a fast component immediately after the injection, which was identical with the decrease of the resp. enzyme activity; and a slow component (half-life 106 min), which in both cases proved to be identical with the half-life of di-iodo-tyrosine. In experiments with amylase, the excretion of protein-free 125I-activity started later than with lipase. The radioactivity of 125I-labelled lipase was taken up faster by brush-border-vesicles than that of 125I-amylase. Liberation of protein-free 125I-activity from both enzymes occurred at the same rate. At the end of the experiments the kidneys had no lipase or amylase activity, but they contained 5.4% (lipase), 3.8% (amylase) of the injected radioactivity.(ABSTRACT TRUNCATED AT 250 WORDS)

Amylases↗
PubMed2005

Changes in the activity of amylase, peroxidase and catalase in beech (Fagus orientalis Lipsky) during dormancy and growth.

Activities of peroxidase, amylase and catalase were analyzed on beech (Fagus orientalis Lipsky) during one year to determine relationship between these enzymes with the period of dormancy and growing season. Results showed that amylase activity was high but catalase and peroxidase activities were low during the growing season. Peroxidase and catalase activities increased from July to November whereas amylase activity started to decrease at the same time, which means that the plants were prepared themselves to be dormant and the hardening was happened. The peroxidase maximum activity was in November, which is an important sign of dormancy and completing hardening in plant. The dormancy released from February along with decrease of catalase activity. At the beginning of growing season, correlation between amylase and catalase was increased. Amylase activity also increased gradually. No significant correlation between amylase-catalase and amylase-peroxidase activities was found at the period of dormancy. In our study, we found that the seasonal activity of enzymes such as peroxidase, catalase, and amylase, also correlation between these enzymes could be an important factor for the detection the period of dormancy and growing season.

Amylases↗
PubMed2004

[Validity of serum amylase and lipase in the differential diagnosis between acute/acutized chronic pancreatitis and other causes of acute abdominal pain].

BACKGROUND: Raised serum amylase and lipase levels are observed in several abdominal diseases. AIM: Assessing the validity of serum amylase and lipase for the differential diagnosis between acute pancreatitis/acutized chronic pancreatitis, biliary tract disease, perforated gastroduodenal ulcer and acute appendicitis. PATIENTS E METHODS: Prospective study including 134 individuals: 38 with acute pancreatitis/acutized chronic pancreatitis, 35 with biliary tract disease, 17 with perforated gastroduodenal ulcer and 44 with acute appendicitis, mean age (standard deviation) of 42.4 +/- 17.7, 46.7 +/- 18.3, 47.8 +/- 12 and 33.7 +/- 17.8 years, respectively. Serum amylase and lipase were determined at admission to the emergency department. RESULTS: For the diagnosis of acute pancreatitis/acutized chronic pancreatitis, when the cutt-off levels of serum amylase were set at the upper normal range level or up to 5-fold as high, the sensitivity decreased from 92% to 74%, the specificity increased from 85% to 99%, the positive predictive value increased from 71% to 97%, and the negative predictive value decreased from 96% to 91%. For serum lipase levels similar figures were obtained for sensitivity and negative predictive value, but the specificity and positive predictive value were lower. When the combination of raised serum amylase or lipase were analyzed, a minor increase was observed in sensitivity and negative predictive value. CONCLUSIONS: For the diagnosis of acute pancreatitis/acutized chronic pancreatitis: 1) the best cut-off level for both tests was 2-times the upper normal range; 2) the sensitivities of serum amylase and lipase were similar; 3) the specificity and positive predictive value of serum amylase were slightly higher than observed for serum lipase; 4) the sensitivity but not the specificity increased when at least one between amylase or lipase was raised.

Abdominal Pain↗
PubMed1995

Adrenalectomy induces a decrease in the light scatter properties and amylase content of isolated zymogen granules from rat pancreas as analyzed by flow cytometry.

The effect of glucocorticoid deprivation induced in male rats by adrenalectomy on the pancreatic zymogen granules was studied. Zymogen granules were purified from control, sham-operated and adrenalectomized animals studied 1, 3 and 7 days after surgery. The zymogen granules were characterized by flow cytometry, and in each granule the size (based on the forward or low angle light scatter (FSC) parameter), membrane complexity (based on side or 90 degrees light scatter (SSC) parameter) and amylase content were evaluated. Amylase content/DNA ratio in pancreatic homogenates was also analyzed. The zymogen granules of the control rats were found to be distributed in two populations: a major one-R1 (95.45 +/- 1.21%)-containing zymogen granules with a smaller mean size and complexity, and a minor population-R2 (4.45 +/- 0.24%)-the granules of which had a mean size which was larger and more complex. At day +1 after adrenalectomy the zymogen granules were significantly (P < 0.05) smaller than those of control animals. The R2 zymogen granules were similar to those from R1 as regards their size, but were more complex, suggesting that the immediate effect of glucocorticoid deprivation is to induce a depletion of the larger granules presumably belonging to the R2 population. The amount of amylase per granule did not vary at day +1 after adrenalectomy, although the amylase content/size ratio per granule was significantly (P < 0.001) increased. This mechanism could be explained in terms of the existence of a bypass defined in the adrenalectomized animals between the granular content and cytosolic enzymes. Prolongation of the adrenalectomy period to 3 and 7 days resulted in a progressive increase in zymogen granule size and complexity, both parameters showing similar characteristics to those of the controls at day +7 after adrenalectomy. However, the percentage of zymogen granules within the R1 and R2 populations was clearly different from that of controls since the R2 population was much more numerous (11.25 +/- 0.75% and 15.25 +/- 1.15% (adrenalectomized rats at days +3 and +7 respectively) versus 4.45 +/- 0.24% (controls)). An increase in the content of amylase per DNA was observed in adrenalectomized rats at day +1 although this transient effect cannot be related to glucocorticoid deprivation because it was also observed in sham-operated rats (day +1). However, a significant reduction, nearly 64%, in the amylase content/DNA ratio is produced by the absence of glucocorticoids 7 days after adrenalectomy and this is associated with a reduction in the content of amylase in each individual zymogen granule which reaches a minimum 3 days after adrenalectomy. It should be noted that, despite this, the enzyme concentration in each granule remains constant as there is a parallel decrease in the zymogen granule amylase content and size.

Adrenalectomy↗
PubMed1991

Dynamic changes in the rate of amylase release induced by various secretagogues examined in isolated rat parotid cells by using column perifusion.

Isolated parotid acinar cells were perifused in small columns by embedding them in Bio-Gel P-2 beads as an inert supporting matrix, and the effect of carbamylcholine, substance P, and isoproterenol on the rate of amylase release was examined by measuring amylase activity in the effluent. Amylase release by continuous stimulation with carbamylcholine and substance P was biphasic. They caused a rapid and large increase in the rate of amylase release that reached maximum 30 to 60s after the onset of stimulation, followed by a rapid decline to a lower sustained level that was maintained as long as the agonists were present. The rapid decline in the rate of amylase release was due to rapid development of refractoriness. Repeated 1 min pulse stimulation with these secretagogues showed that recovery from refractoriness was also rapid in onset, and 1 min of washout was sufficient to cause significant recovery from refractoriness for both carbamylcholine and substance P. Recovery, however, was not complete after 10 min of washout. Amylase release by continuous stimulation with isoproterenol, on the other hand, developed more slowly with the peak rate being attained at about 6 min after the onset of stimulation. Refractoriness was not observed in the effect of isoproterenol. The maximum effect in the rate of amylase release attained by carbamylcholine or substance P was higher than that by isoproterenol. These results suggest that the apparent small effect of carbamylcholine and substance P on amylase release reported earlier by using batch systems is probably due to the rapid development of refractoriness to these secretagogues, but not to isoproterenol.

Amylases↗
PubMed1995

Potentiation of cholecystokinin-induced amylase release by peptide VIP in guinea pig pancreatic acini.

The mechanism of the potentiating effect of vasoactive intestinal peptide (VIP) on cholecystokinin (CCK-8)-induced amylase release was studied in isolated and perifused pancreatic acini of the guinea pig. VIP (30 pM-10 nM) potentiated CCK-8 (100 pM)-induced amylase release. Unexpectedly, VIP inhibited CCK-8-induced intracellular Ca2+ oscillations. Forskolin (10 microM), an activator of adenylate cyclase, potentiated CCK-8 (100 pM)-induced amylase release with a time course similar to that observed with VIP. Caffeine (20 mM) inhibited both amylase release and Ca2+ oscillations in response to CCK-8, suggesting that inhibition of Ca2+ oscillations does not necessarily lead to a potentiation of amylase release. When intracellular Ca2+ concentration ([Ca2+]c) was raised by thapsigargin (10 microM), a selective inhibitor of Ca(2+)-ATPase in the endoplasmic reticulum (ER), VIP (10 nM) induced significantly greater amylase release than that induced by VIP alone. When [Ca2+]c was lowered by preincubation with BAPTA-AM (25 microM), a cell-permeant Ca2+ chelator, VIP-induced amylase release was completely abolished. These results suggest that VIP, in spite of its inhibitory action on Ca2+ oscillations, facilitates a Ca(2+)-dependent process distal to the increase in [Ca2+]c to potentiate CCK-8-induced amylase release.

Amylases↗
PubMed1980

The relative values of serum immuno-reactive trypsin concentration and total amylase activity in the diagnosis of mumps, chronic renal failure, and pancreatic disease.

Fasting serum concentrations of trypsin and amylase activity have been compared in 107 subjects, including 18 controls and patients with mumps, acute pancreatitis, chronic pancreatitis, cancer of the pancreas, and chronic renal failure. There was no significant correlation between amylase activity and trypsin concentrations in any of these groups. In all 12 patients with acute pancreatitis and all 16 with chronic renal failure the serum immuno-reactive trypsin concentrations were elevated. Amylase activity was increased in 87% (20 out of 23) of patients with mumps, but only 13% (3 out of 23) had hypertrypsinaemia suggesting subclinical pancreatitis. In 18 patients with chronic pancreatitis low levels of serum trypsin were measured in 11 (61%), reflecting a decrease in pancreatic acinar mass. In contrast, serum amylase was normal or raised in all 18. Subnormal values of the trypsin to amylase ratio was obtained in 15 (83%). Trypsin levels in 20 patients with carcinoma of the pancreas were abnormal in 11 (55%). Six (30%) had abnormal amylase levels. It is concluded that it is more useful to measure the serum trypsin concentration than the amylase activity in the diagnosis of both mumps-pancreatitis and chronic pancreatic disease and that the trypsin to amylase ratio is more sensitive than either enzyme alone in the diagnosis of chronic pancreatitis.

Adult↗
PubMed1975

Radioimmunoassay of serum pancreatic amylase in normal and pancreatectomized pigs (38504).

A double antibody radioimmunoassay has been developed that is capable of assaying and discriminating small amounts of pancreatic amylase even in the presence of amylase isoenzymes. Assays on adult pigs indicate a mean serum concentration of pancreatic amylase of 2.4mug/ml. To date, no other technique can offer such a discrimination of the pancreatic amylase in the circulation. Following pancreatectomy, the amount of radioimmunoassayable amylase in the circulation disappeared within 48 hr. This was reflected by a simultaneous decline in the serum amylase enzyme activity. Within 48 hr after pancreatectomy, the serum amylase enzyme activity had declined 60%. Thus, in pigs, the pancreas contributes significantly to the circulating amylase levels.

Amylases↗
PubMed1986

Distribution of alpha-amylase activity in selected broiler tissues.

In an examination of broiler alpha-amylase, significant variation in the serum enzyme activity level was noted, adult levels were lower than those of young chicks. Analysis of alpha-amylase activity in various body fluids and tissues of 11-day and 7-week-old broilers indicated that the liver cannot be considered a source of alpha-amylase, although there was activity in both liver tissue and bile of 10 units/g wet weight and 35 units/100 ml, respectively. Fluid from the oral cavity had low levels of alpha-amylase activity, less than 100 units/100 ml, which decreased with age, indicating that the salivary glands may synthesize some alpha-amylase but are not a primary source. Sonication of the pancreatic homogenates was found to significantly increase the apparent activity of alpha-amylase 35-fold over unsonicated homogenates. The pancreas was the major source of alpha-amylase with activities ranging from 89 X 10(2) to 445 X 10(2) units/g wet weight. The level of activity increased with age of the bird. The electrophoretic zymograms of serum, liver, and pancreatic homogenates indicate a similar pancreatic origin for the alpha-amylase found in each tissue or fluid.

Aging↗
PubMed2005

Amylase level in extrahepatic bile duct in adult patients with choledochal cyst plus anomalous pancreatico-biliary ductal union.

AIM: To investigate the relationship between pancreatic amylase in bile duct and the clinico-pathological features in adult patients with choledochal cyst and anomalous pancreatico-biliary ductal union (APBDU). METHODS: From 39 patients who underwent surgery for choledochal cyst between March 1995 and March 2003, we selected 15 adult patients who had some symptoms and were radiologically diagnosed as APBDU, and their clinico-pathological features were subsequently evaluated retrospectively. However, we could not obtain biliary amylase in all the patients because of the surgeon's slip. Therefore, we measured the amylase level in gall bladder of 10 patients and in common bile duct of 11 patients. RESULTS: Levels of amylase in common bile duct and gall bladder ranged from 11,500 to 212,000 IU/L, and the younger the patients, the higher the biliary amylase level (r = -0.982, P<0.01). Pathologically, significant correlation was found between the size of choledochal cyst and the grade of inflammation (r = 0.798, P<0.01). And, significant correlation was found between the level of amylase in gall bladder and the grade of hyperplasia. On the other hand, there was no correlation to the age of symptomatic onset or inflammatory grade (r = 0.743, P<0.05). Level of lipase was elevated from 6,000 to 159,000 IU/L in bile duct and from 14,400 to 117,000 IU/L in the gall bladder; however, there was no significant correlation with age or clinico-pathological features. CONCLUSION: The results support the notion that amylase has a particular role in the onset of symptoms, and suggest that a large amount of biliary amylase induces early onset of symptom, thereby making early diagnosis possible.

Adult↗
PubMed2001

Development and validation of a monoclonal based immunoassay for the measurement of fungal alpha-amylase: focus on peak exposures.

The inhalation of flour dust has been implicated in the induction of sensitisation and elicitation of respiratory symptoms, such as asthma in bakers. In addition to the cereal allergens present in wheat flour, enzymes in flour improvers, in particular fungal alpha-amylase, are now known to be a significant cause of respiratory allergy in the baking industry.A monoclonal antibody based enzyme-linked immunoassay (ELISA) was developed using two monoclonal antibodies that recognised two distinct epitopes of the fungal alpha-amylase enzyme. The ELISA had an inter-assay variation of 12.0% at 1360 pg/ml and 12.8% at 564 pg/ml and intra-assay variation of 4.9% at 1340 pg/ml and 6.1% at 504 pg/ml. The assay had a sensitivity of 200 pg/ml. Competitive inhibition assays confirmed that the monoclonal antibodies had no cross reactivity with other enzymes used in the baking industry and could distinguish added fungal alpha-amylase from cereal amylase. We assessed the levels of exposure to dust, total protein and fungal alpha-amylase in four UK bakeries ranging in size and technical capabilities. Within the bakeries we surveyed, workers were exposed to variable levels of inhalable dust (0.8-39.8 mg/m3), total protein (0-5.7 mg/m3) and fungal alpha-amylase (0-29.8 ng/m3). Consecutive 15 min personal samples taken over a 1 h period demonstrated that the ELISA could measure fungal alpha-amylase exposure in such a 15 min period. Short term peak exposures to fungal alpha-amylase could be identified which may contribute to the sensitisation in individuals who appear to have low exposure levels if measured over a full shift period.

Antibodies, Monoclonal↗
PubMed1992

Effects of calmodulin inhibitors on amylase secretion from rat pancreatic acini.

To investigate the role of calmodulin in stimulus-secretion coupling in pancreatic acinar cells, we studied the effects of W-7, a calmodulin inhibitor, and KN-62, a specific inhibitor of Ca2+/calmodulin-dependent protein kinase II (Ca2+/CaM kinase II), on amylase secretion from rat pancreatic acini. Calmodulin inhibitor (W-7, 100 microM) and Ca2+/CaM kinase II inhibitor (KN-62, 10 microM) reduced amylase secretion stimulated by cholecystokinin (CCK) or carbachol. W-7 and KN-62 also inhibited amylase secretion stimulated by both calcium ionophore (A23187) and phorbol ester (12-O-tetradecanoylphorbol-13-acetate, TPA). To clarify the role of calmodulin in the interaction of intracellular mediators, pancreatic acini were permeabilized with streptolysin O. Following permeabilization, amylase secretion was stimulated by submicromolar free Ca2+, and this Ca(2+)-dependent amylase secretion was enhanced by guanosine 5'-[gamma-thio]triphosphate (GTP gamma S), TPA or cyclic adenosine 3',5'-monophosphate (cAMP). W-7 and KN-62 had no effects on amylase secretion stimulated by Ca2+ alone, but inhibited the enhancement in Ca(2+)-dependent amylase secretion by GTP gamma S, TPA or cAMP. These data suggest that calmodulin plays an important role in Ca(2+)-dependent amylase secretion from pancreatic acinar cells and in the interaction between Ca2+ and other intracellular messengers.

1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine↗
PubMedDate not supplied

[Acid gamma-amylase of rabbit and human brain].

Preparations of acidic gamma-amylase, which cleaved glycogen and maltose, were isolated from human and rabbit brain tissues. The specific activity of the gamma-amylase preparations from human brain was approximately twice higher than the activity of the enzyme from rabbit brain. In degradation of glycogen gamma-amylases from human and rabbit brain had the pH optima at pH 4.9 and 4.6 and with maltose as a substrate- at pH 4.3 and 4.1, respectively. gamma-Amylases from both sources possessed the high stability in presence of monovalent cations. K+ distinctly increased the cleavage of glycogen by gamma-amylase from human and rabbit brain. alpha, alpha-Trehalose and alpha-menthyl glucoside proved to be inhibitors of the glucoamylase activity of the enzymes from both sources. Km values of the gamma-amylases for glycogen were equal to 19.3 mM 19.8 and for maltose -5.54 mM and 5.78 mM, respectively. The data obtained suggest that acidic gamma-amylases from human and rabbit brain are similar to acidic gamma-amylases from other sources.

Amylases↗
PubMedDate not supplied

Establishment and characterization of amylase-producing lung adenocarcinoma cell line, IMEC-2.

BACKGROUND: Few studies have successfully established an amylase-producing lung cancer cell line or have examined its cytological, biochemical and biological features. PATIENTS AND METHODS: Cancer cells, isolated from pleural effusion using a gradient method, were cultivated. RESULTS: Amylase production from the newly established cell line was confirmed by positive staining for alpha-amylase and increased amylase levels in the culture supernatant. Electron microscopy revealed zymogen granule-like structures. Sialylation of salivary-type amylase was confirmed directly from the cell line by examining the neuraminidase sensitivity and amylase elution profile under high-performance liquid chromatography. Neither EGFR or KRAS mutation were found. CONCLUSION: This cell line offers a useful tool for analyzing the pathogenesis and pathophysiology of amylase-producing lung cancers. Moreover, it might be useful for probing the metastasis and invasiveness of lung cancer cells and for developing an early diagnostic method based on sialylated salivary-amylase production.

Adenocarcinoma↗
PubMed1990

Serum amylase in patients with renal insufficiency and renal failure.

Results vary with regard to the upper limits of serum amylase seen in patients with renal failure, and very little has been reported with patients with renal insufficiency not yet requiring dialysis. To determine the level of serum amylase elevation in renal insufficiency and renal failure, we determined serum amylase values in 128 subjects with creatinine clearances less than 90 ml/min. Serum amylase remained in the normal range when creatinine clearance was greater than 50 ml/min, and did not become elevated until creatinine clearance was less than 50 ml/min. The highest serum amylase recorded in the absence of acute pancreatitis was 503 IU/L (normal, less than 128 IU/L). Serum lipase and trypsin values paralleled those for serum amylase; values remained normal when creatinine clearance was greater than 50 ml/min, and were normal or elevated when creatinine clearance was less than 50 ml/min. These results indicate that elevations of serum amylase (i.e., amylase greater than 128 but less than 500 IU/L) in asymptomatic patients with impaired renal function are not evident until creatinine clearances fall below 50 ml/min, and probably do not represent acute pancreatitis.

Acute Disease↗
PubMed1991

Immunohistochemical demonstration of pancreatic alpha-amylase and trypsin in intrahepatic bile ducts and peribiliary glands.

Epithelia of intrahepatic bile ducts and peribiliary glands were immunohistochemically examined for pancreatic alpha-amylase and trypsin in 54 normal autopsied livers. alpha-Amylase was evaluated with a polyclonal antibody, and trypsin was assayed with both polyclonal and monoclonal antibodies. alpha-Amylase was observed in large ducts, septal ducts and peribiliary glands in most livers and was seen in interlobular ducts in seven (13%) livers. Trypsin immunoreactivity with the polyclonal antibody was observed in peribiliary glands in 21 (39%) livers; it was absent in intrahepatic bile ducts in all but one liver. Trypsin immunoreactivity with the monoclonal antibody was present in large ducts, septal ducts and peribiliary glands in about 70% of the livers and was seen in interlobular ducts in two (4%) livers. Bile ductules were always negative for the two antigens. Some epithelia of peribiliary glands positive for both alpha-amylase and trypsin histologically resembled pancreatic acinar cells. alpha-Amylase and trypsin immunoreactivities of intrahepatic biliary epithelia and pancreatic aninar cells were eliminated by absorption of primary antibodies by alpha-amylase or trypsin, suggesting the specificities of the immunoreactivities. These data suggest that epithelia of intrahepatic large ducts, septal ducts and peribiliary glands contain pancreatic alpha-amylase in most livers and that they contain trypsin in about 70% of livers. alpha-Amylase and trypsin may be secreted into intrahepatic bile duct lumens, thereby exerting important effects on the physiology of the intrahepatic biliary tree and hepatic bile.

Adult↗
PubMed1991

Expression of alpha-amylase isozymes in human thyroid tissues.

Expression of alpha-amylase genes in thyroid tissues was studied by assaying the total amylase activity as well as by using immunohistochemical and Northern blot analysis. The amylase genes expressed were determined by a combination of the polymerase chain reaction (PCR) and blot analysis using synthetic probes specific for the three known amylase isozyme complementary DNAs. The samples consisted of tissues from 18 human thyroid carcinomas (11 well-differentiated carcinomas, 2 poorly differentiated carcinomas, 1 anaplastic carcinoma, and 4 medullary carcinomas) and 9 specimens of nonmalignant thyroid tissue (2 were from nontumorous regions of resected glands and 7 were thyroid tissue from a patient with Graves' disease). Salivary-type amylase was expressed at a relatively high level in nonmalignant thyroid tissue and well-differentiated carcinoma and could be detected by Northern blot analysis. In poorly differentiated carcinoma, it was detected only by the PCR, while in anaplastic or medullary carcinoma, it was not detected even by the PCR. Thus, the expression of salivary-type amylase was characteristic of well-differentiated follicular cells. These observations suggest that salivary-type amylase expression may be a marker for identifying the histogenesis and stage of differentiation of thyroid cancer. In addition, the AMY2B gene product was detected in all different types of cells examined, although its expression was only detectable by the PCR. Pancreatic type amylase was not detected in any of the samples.

Adult↗