Wall Street had a short response to anyone who wanted to borrow money this week: Come back later.

Companies that issue bonds and short-term debt were largely shut out of the credit markets. But so were cities and counties that rely on short-term notes to pay for routine operations while waiting for tax revenues to arrive, leaving them to search for other financing.

Among the $6 billion in new municipal debt issues anticipated at the beginning of the week, only about $100 million actually came to the market, and the rest was postponed, said John V. Miller, chief investment officer at Nuveen Asset Management, a municipal bond investment firm.

Despite some slight signs of improvement on Friday, Mr. Miller and others said they were worried that the markets could remain unsettled for some time. If the dysfunction persists, some municipalities might be caught in a financial vise, imperiling local projects and even making it harder to meet payrolls.

Key borrowing rates slipped modestly on Friday. Investors said the market was unnerved by news that the government had seized Washington Mutual, the nation’s largest savings and loan. Many were also disappointed that policy makers had been unable to reach an agreement on a Treasury Department proposal to buy troubled assets from financial institutions.