Optimal conditions necessary for the cytochemical demonstration of megakaryocyte (Mk) and platelet acid phosphatase (AP) were determined. Methanol, a constituent of fixatives commor)Iy used in AP cytochemistry, was found to inhibit MkAP, and the degree of inhibition varied with Mk maturity. Immature Mk contained predominantly methanol-resistant AP, and mature Mk, predominantly methanol-sensitiv...

Optimal conditions necessary for the cytochemical demonstration of megakaryocyte (Mk) and platelet acid phosphatase (AP) were determined. Methanol, a constituent of fixatives commor)Iy used in AP cytochemistry, was found to inhibit MkAP, and the degree of inhibition varied with Mk maturity. Immature Mk contained predominantly methanol-resistant AP, and mature Mk, predominantly methanol-sensitiv...

Two morphologically distinct types of murine megakaryocyte (MK) colonies are present after three to seven days in soft agar culture: (a) big-cell” colonies composed of ten to 30 large, mature-appearing megakaryocytes and (b) “heterogeneous” colonies consisting of approximately 1 00 or more cells at various stages of differentiation. Cytochemical and immunocytochemical techniques were used to st...

The DNA content of rat bone marrow megakaryocytes (MK) was studied by Feulgen photometry, following whole body irradiation with 2 Gy. The DNA measurements were preceded by acetylcholinesterase staining to avoid missing the smaller 2N-8N MK. The number of 2N-8N MK declined immediately following irradiation, whereas the number of 16N-64N MK remained normal for 4 days before decreasing. The number...

Midkine (MK), a heparin-binding growth factor, is overexpressed in a wide range of human carcinomas and is believed to contribute to tumorigenesis and tumor progression. To develop an antitumor reagent, we designed a phosphorothioate antisense oligodeoxynucleotide molecule based on the secondary structure of MK mRNA. The antisense MK at the dosage of 5 M suppressed MK production by CMT-93 mouse...

The midkine (MK) family consists of only two members, namely MK and pleiotrophin (PTN). MK and PTN share receptors and biophysical characteristics, such as a heparin-binding property. MK and PTN exert several biological activities, which include fibrinolytic, anti-apoptotic, mitogenic, transforming, angiogenic, and chemotactic ones. These activities suggest that these growth factors are involve...

The iron uptake in vitro of red cells from mice with hereditary microcytic anemia (gene symbol mk) was studied to examine the hypothesis of a generalized impairment of cellular iron uptake in this conidition. Reticulocyte-rich red cells from anemic (mk/mk) and acutely bled normal (+/+) mice were incubated in 59Fe-labeled mouse plasma and the radioiron uptake measured. The 59Fe uptake of the mk/...

Systemic or hindbrain administration of MK-801, a noncompetitive N-methyl-D-aspartate receptor antagonist, increases meal size. To examine whether MK-801 enhances intake by increasing gastric emptying, we administered MK-801 (2.0 microg/3.0 microl) into the fourth ventricle [intracerebroventricular (ICV)] and measured feeding and gastric emptying of 5-ml NaCl or 15% sucrose loads. In a parallel...

Midkine (MK), a heparin-binding growth factor, is overexpressed in a wide range of human carcinomas and is believed to contribute to tumorigenesis and tumor progression. To develop an antitumor reagent, we designed a phosphorothioate antisense oligodeoxynucleotide molecule based on the secondary structure of MK mRNA. The antisense MK at the dosage of 5 microM suppressed MK production by CMT-93 ...

UNLABELLED Midkine (MK) is a growth factor with neurotrophic and neurite outgrowth activities. It was expressed in the peri-ischaemic area in the acute phase of cerebral infarction in rat brains. Astrocytes were the origin of MK in this occasion. MK has been assessed in terms of its effects on neural injury. The administration of MK into the lateral ventricle immediately prior to ischaemia prev...