Brain staining of pregnant fish (IMAGE) Society for Experimental Biology Caption Brain staining of pregnant fish. On the left is the Nissl staining use to determine neuron morphology and on the right is ki67 staining which stains for cell proliferation. Credit Tiffany Ernst Usage Restrictions Credit must be given to the creator. Adaptations must be shared under the same terms. License CC BY-SA Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.